Speciality
Spotlight

 




 

Nuclear Medicine

 

 




  • Ramos CD, Zantut-Wittmann DE, Tambascia MA, et al (Campinas State Univ, Brazil)

    Thyroid Suppression Test With L-Thyroxine and [99
    m
    Tc] Pertechnetate

    Clin Endocrinol (Oxf) 52: 471-477, 2000

          

    This article evaluates the efficacy of L-thyroxine as a TSH suppressor and technetium 99m
    (99mTc) pertechnetate as a radiopharmaceutical agent for diagnosing autonomous functioning thyroid nodules.

        

    15 healthy volunteers (21-35 years) and 20 patients (27-83 years) were studied (7 autonomic functioning non-toxic nodules, 3 autonomic functioning toxic nodules, 7 with Graves’ disease and 3 with non- autoimmune diffuse toxic goiter). Baseline thyroid uptake and imaging were done 20 minutes after an IV injection of 370 MBq of
    99mTc pertechnetate, followed by a single daily dose of L-thyroxine (2
    mg/kg) for 10 days. At this time, thyroid uptake and imaging were repeated.

        

    The mean reduction in 99mTc pertechnetate uptake after L-thyroxine suppression was 75.8% from baseline in the control group. All subjects were euthyroid, and there were no adverse effects. The uptake declined by 39% in 10 patients, was unchanged in 2 and increased in 8.

         

    This method effectively demonstrates autonomous thyroid tissue. It is as effective as the original
    T3 suppression test, but is more convenient because of ease of hormonal intake, low dosimetry and short stay. There are no adverse effects.

          

  • Erdil
    TY, Onsel C, Kanmaz B, et al (Marmara Univ, Istanbul, Turkey; Istanbul Univ, Turkey; Hacettepe Univ, Ankara, Turkey)

    Comparison of 99mTc-Methoxyisobutyl Isonitrile and
    201TI Scintigraphy in Visualization of Suppressed Thyroid Tissue

    J Nucl Med 41: 1163-1167, 2000

          

    201TI (thallium) and MIBI (methoxyisobutyl isonitrile) have been compared in the visualization of suppressed thyroid tissue in patients with a solitary toxic autonomously functioning thyroid nodule
    (AFTN).

           

    32 patients with toxic AFTNs seen on 99mTc pertechnetate screening underwent MIBI and
    201TI scanning within 3 days. Scintigrams were analyzed semiquantitatively as well as visually. In the semiquantitative analysis, regions of interest (ROIs) were produced over the nodule (N) and contralateral normal lobe (E) and the mean ROI counts were made.

         

    The mean N/E uptakes were 11.37 for partechnate and 4.76 for MIBI and 1.63 for
    201TI in triiodothyronine (T3) plus thyroxine
    (T4) hyperthyroid patients.

          

    In T3 hyperthyroid patients these values were 9.46, 2.73 and 1.57 respectively.
    201TI uptake of suppressed thyroid tissue compared with AFTN was more marked and significantly higher than that of MIBI for both groups.

         

    When the N/E uptakes of the two groups were compared neither pertechnate nor
    201TI differed significantly. However, the N/E uptake of MIBI in
    T3 + T4 hyperthyroid patients was significantly greater than in the
    T3 group.

         

    201TI is better than MIBI in visualizing suppressed thyroid tissue in patients with a toxic thyroid nodule. An increased metabolic rate in the follicular cells of AFTNs in
    T3 + T4 hyperthyroid patients compared with that in
    T3 hyperthyroid patients may be responsible for the greater N/E for MIBI compared with that of
    201TI.

          

  • Reschini E, Matheoud R, Canzi C, et al (Ospedale Maggioreo, Milano, Italy; Ospedale Fatebenefratelli, Milano, Italy; Ospedale S Pio X, Milano, Italy; et al)

    Dosimetry Study in Patients With Autonomous Thyroid Nodule Who Are Candidates for Radioiodine Therapy

    J Nucl Med 40: 1928-1934, 1999

         

    Autonomous thyroid nodules are treated successfully with radioiodine therapy. The development of hypothyroidism after such therapy may be related to extranodular dosing.

          

    17 patients with elevated free thyroxine or free triiodothyronine levels and 9 patients with normal levels were studied. Radioiodine turnover parameters were determined for the nodule and for the contralateral lobe (extranodular tissue).

           

    123I was used and its biological half-life was converted into the effective half-life of
    131I. Scintigraphy or US was used to measure the
    131I volumes of nodule and lobe. The images were overexposed to reveal the lobe, a technique that made the lobe especially noticeable at 24 hours.

          

    Both in uptake and in dismission (biological half-life) the nodules varied considerably. 14 of the 26 patients had diminished levels, and in 3, the value was extremely short. Uptake of radioiodine was very low overall. The biological half-life was prolonged in the lobe when compared with the nodule, and the lobe’s uptake curve differed.

          

    The amount of radiation the lobe received was more than one tenth that received by the nodule. The dose received by extranodal tissue is higher than has been assumed, so it is reasonable to assume that posttreatment hypothyroidism may occur.

          

  • Yeung
    HWD, Humm JL, Larson SM (Mem Sloan-Kettering Cancer Ctr, New York)

    Radioiodine Uptake in Thyroid Remnants During Therapy After Tracer Dosimetry

    J Nucl Med 41: 1082-1085, 2000

          

    Before undergoing radioiodine therapy of residual tumor or thyroid remnant after thyroidectomy, patients usually have dosimetry with
    131I to assess disease and to calculate
    uptake.

          

    From this study the therapeutic dose of 131I is evaluated. Whether the initial dosimetric dose affects the subsequent uptake of the therapeutic dose (stunning) has not been well studied. The sequential uptake of both the tracer and therapeutic dose of
    131I was examined in a series of 12 consecutive patients.

         

    The patients were first subjected to thyroid dosimetry with
    131I followed by a therapeutic
    131I dose. The neck activity was calculated by the region-of-interest method in each case. Uptake after
    the therapeutic dose was expressed as a percentage of uptake after the diagnostic dose (% T/D).

          

    Of the 16 thyroid lesions in this series, 13 showed reduced uptake from the therapeutic dose, 2 remained the same, and 1 had increased uptake. The % T/D ranged from 7.0% to 388.5%. If the lesion with increased uptake was excluded from the data set, the range was 7.0% to 102.1% with an average of 50%.

         

    Linear regression between the percentage uptake of the diagnostic dose to the percentage uptake of the therapeutic dose results in a slope of 0.42, with a correlation coefficient of 0.75.

         

    The uptake of the therapeutic dose of 131I into thyroid lesions was significantly less than that predicted by the tracer dose of
    131I in most patients. The stunning effect was present even for tracer doses of
    131I as low as 37.0 MBq (1
    mCi).

          

  • Cholewinski SP, Yoo KS, Klieger PS, et al (Univ of Rochester, NY)

    Absence of Thyroid Stunning After Diagnostic Whole-Body Scanning With 185 MBq
    131I
     

    J Nucl Med 41: 1198-1202, 2000


          


    This study evaluates the effect of a 185 MBq diagnostic dose of
    131I when administered 72 hours before
    131I ablation therapy. 122 patients treated by thyroidectomy for differentiated thyroid carcinoma were given 185 MBq diagnostic dose of 131I followed by a whole body diagnostic scan at 72 hours.

         

    Most patients were hospitalized and given 131I ablation therapy (5550 MBq) the same day as the diagnostic scan. A post-ablation whole body scan was obtained at 72 hours for comparison with the previous scan.

         

    No stunning effect was visually apparent when the ablation dose
    (131I) was dose on the day of the diagnostic scan completion. Therefore whole body scanning can yield high diagnostic accuracy and subsequent ablation success without concern for thyroid stunning.

          

  • Oyen
    WJG, Verhagen C, Saris E, et al (Univ Hosp Nijmegen, The Netherlands)

    Follow-Up Regimen of Differentiated Thyroid Carcinoma in Thyroidectomized Patients After Thyroid Hormone Withdrawal 

    J Nucl Med 41: 643-646, 2000

         

    This article attempts to optimize the diagnostic protocol for the follow-up of thyroidectomized patients after thyroid carcinoma.

         

    254 patients followed up for a mean 2.7 years were studied retrospectively. Patients underwent a low dose
    131I diagnostic procedure under hyperthyroid conditions, thallium 201
    (201Tl) scintigraphy and assessment of thyroglobulin under hypothyroid conditions. A total of 254 preablation and 586 follow-up studies were evaluated.

         

    Low-dose 131I screening before ablation was useful for estimating the size of thyroid remnants. Thyroglobulin concentrations <10 pmol/lL indicated absence of metastases. Undetectable thyroglobulin concentrations after ablation demonstrated the absence of tumor recurrence.

         

    Thyroglobulin levels >10 pmol/L indicated local recurrence or metastases, which required high dose
    131I therapy. In such patients
    201Tl imaging did not contribute to patient management.

         

    The role of 201Tl imaging in such patients is limited. It may be considered when low dose
    131I screening is negative and thyroglobulin levels are increased or cannot be evaluated because of autoantibodies against
    thyroglobulin.


          

  • Ng
    DCE, Sundram FX, Sin AE (Singapore Gen Hosp) 

    99mTc-Sestamibi and 131I Whole-Body Scintigraphy and Initial Serum Thyroglobulin in the Management of Differentiated Thyroid Carcinoma 

    J Nucl Med 41: 631-635, 2000

            

    360 patients were studied prospectively. 99mTc-sestamibi whole-body scanning was done at least 5 weeks after thyroidectomy, followed by
    131I whole-body scanning. No thyroxine suppression was given for 5 weeks. Radiologic and histopathologic examinations were done to determine the presence of metastases.

          

    The initial serum thyroglobulin levels were less than 30 ng/mL in 71.9% of the patients (group I), and 28.1% had levels of 30 ng/mL or more (group II). 82 of the 259 patients (group I) had positive
    99mTc-sestamibi scans, and 113 had positive
    131I scans.

          

    Of these patients with positive 131I scans, 71.7% also had positive
    99mTc-sestambi scans. Of patients with positive
    99mTc-sestamibi scans, 98.8% also had positive
    131I scans. 81 of the 101 patients in Group II had positive
    99mTc-sestamibi scans, and 97 had positive
    131I scans. Of the patients with positive
    131I scans, 83.5% also had a positive
    99mTc-sestamibi scan. 

         

    All patients with positive 99mTc-sestamibi scans also had positive
    131I scans. In group II, 27.2% had thyroid remnants and 68.8% had lymph node disease or metastases.
    131I scanning demonstrated more thyroid remnants and lung metastases than did
    99mTc-sestamibi scanning.

          

    131I scans are more sensitive than
    99mTc-sestamibi scans in detecting thyroid remnants and lung metastases. However,
    99mTc-sestamibi scanning appears to be more useful for demonstrating lymph node disease before initial
    131I therapy.

            

  • Erdil
    TY, Ozker K, Kabasakal L, et al (Marmara Univ, Istanbul, Turkey; Med College of Wisconsin, Milwaukee; Istanbul Univ, Turkey; et al)

    Correlation of Technetium-99m MIBI and Thallium-201 Retention in Solitary Cold Thyroid Nodules With Postoperative Histopathology

    Eur J Nucl Med 27: 713-720, 2000

             

    The authors have compared thallium 201 (201TI) imaging with technetium 99m
    (99mTc) methoxyisobutylisonitrile (MIBI) imaging (early and delayed) in the differentiation of benign and malignant thyroid nodules.

           

    40 patients with cold thyroid nodules detected by 99mTc pertechnetate scanning and with dyskaryotic or atypical epithelial cells confirmed by fine-needle aspiration biopsy (FNAC) were studied. The patients underwent MIBI and
    201TI scintigraphy 3 days apart. Subsequently all patients underwent
    thyroidectomy.

          

    A lesion-to-nonlesion ratio on early (ER) and delayed images (DR) was used in the semiquantitative analysis. Also, a retention index (RI) was determined by using the following formula: RI = (DR
    – ER) X 100/ER.

           

    21 patients had well differentiated thyroid cancer, and 19 had benign lesions. The ER did not differ significantly between malignant and benign lesions for
    201TI or MIBI. However, malignant and benign lesions differed significantly in DR and RI with both modalities. The 2 groups did not show any statistical differences except in DR and RI in malignant nodules.

          

    Based on these threshold levels, ER MIBI had a sensitivity of 90.5%, a specificity of 36.8%, and an accuracy of 65%. For DR MIBI, these values were 61.9%, 94.7%, and 77.5% respectively. The RI MIBI had a 95.2% sensitivity, 89.4% specificity, and a 92.5% accuracy. For ER
    201TI, these values were 85.7%, 47.3%, and 67.5%, respectively. The DR
    201TI had an 80.9% sensitivity, 73.6% specificity, and 77.5% accuracy. For RI
    201TI, these corresponding values were 90.5%, 94.7%, and 92.5%.

           

    The DR for MIBI and 201TI is better than the ER for detecting malignant nodules. The RI for both MIBI and 201TI is of more value than the DR for differentiating malignant from benign thyroid nodules.

             

  • Fatourechi V, Hay ID, Mullan BP, et al (Mayo Clinic, Rochester, Minn)


    Are Posttherapy Radioiodine Scans Informative and Do They Influence Subsequent Therapy of Patients With Differentiated Thyroid Cancer?


    Thyroid 10: 573-577, 2000

          

    This study evaluates the efficacy of a posttherapy scans (PTSs) to visualize metastases that may not be apparent on a lower dose diagnostic scan.

          

    81 patients were studied (64 had papillary thyroid cancer, and 17 had follicular thyroid cancer). All patients underwent both a diagnostic whole-body scan and a PTS. A total of 117 PTSs were examined.

          

    At the time of PTS, 68 patients had clinical or radiologic evidence of metastatatic or residual disease. Known disease was located in neck on 63 scans, mediastinum on 23, lung on 35, bone on 14, trachea on 16, esophagus on 5, and brain on 2 scans. Focal areas of abnormal uptake not visualized in diagnostic scans could be seen on 15 PTSs (13%).

          

    Areas with abnormal new uptake included the neck on 5 scans, lung on 5, mediastinum on 4, bone on 2, and adrenal gland on 1 scan. In 9% of patients, PTS findings affected plans for subsequent diagnostic scanning and
    131I therapy or altered the patients’ risk group category.

           

  • Alnafisi NS, Driedger AA, Coates G, et al (Univ of Western Ontario, London; McMaster Univ, Hamilton, Ont)


    FDG PET of Recurrent or Metastatic 131I-Negative Papillary Thyroid Carcinoma


    J Nucl Med 41: 1010-1015, 2000

          

    The authors have evaluated the value of FDG PET in the diagnosis of papillary thyroid cancer with negative
    131I total body scan and increased thyroglobulin levels after total
    thyroidectomy.

         

    11 asymptomatic thyroidectomised patients (for papillary cancer) with negative
    131I total body scan but raised thyroglobulin levels (no thyroxine therapy) were studied. All of them had also been treated by
    131I ablation and all known metastases treated. Imaging failed to demonstrate residual tumor before PET. 

         

    After PET, all underwent CT scan, sonography and biopsy of neck lesions. All patients had FDG uptake in the neck or upper mediastinum (initial scans of 10 and in repeat scan of 1). Sonographically guided biopsy confirmed malignancy in 6 patients, were normal in 1, and was nondiagnostic in 2. 2 did not undergo biopsy. 

         

    Imaging with FDG resulted in treatment modifications in 7, resulting in surgery and external beam radiotherapy in 3, surgery in 1 and external beam radiotherapy in 2. In all those subjected to surgery, histopathology was positive.

         

    FDG PET scan enabled detection of disease in 7 patients out of 11. In conjunction with sonography and biopsy it resulted in the treatment changes in most patients.

          

  • Brandt-Mainz K, Muller SP, Gorges R, et al (Universitatsklinikum Essen, Germany)


    The Value of Fluorine-18 Fluorodeoxyglucose PET in Patients With Medullary Thyroid Cancer


    Eur J Nucl Med 27: 490-496, 2000

          

    The value of fluorine 18 (18F) FDG PET in following up patients with medullary thyroid cancer (MTC) has been investigated. 

         

    20 patients with increased calcitonin levels or sonographic abnormalities in the neck underwent
    18F-FDG PET; findings were validated by histologic evaluation, CT findings, or selective venous catheterization results.

          

    13 of 17 had a tumor detected on 18F-FDG PET and validated by histology or CT. 5 Patients had completely negative scans (PET), including 4 false negative scans. One patient with
    18F-FDG accumulation in pulmonary lesions from silicosis and 1 patient with a neck lesion not subjected to histologic evaluation were excluded from the analysis.

          

    In all 18F-FDG PET detected 12 of 14 metastases in the neck, 6 of 7 in the mediastinum, 2 of 2 in the lungs, and 2 of 2 in bone. None of the diagnostic modalities could localize tumor in 2 patients with increased calcitonin levels. The sensitivity of the
    18F-FDG PET was 76%.

               

  • Angusti T, Codegone A, Pellerito R, et al (Ospedale Mauriziano Umberto I Torino, Italy)


    Thyroid Cancer Prevalence After Radioiodine Treatment of Hyperthyroidism


    J Nucl Med 41: 1006-1009, 2000

          

    Radioiodine therapy may be a risk factor for the misdiagnosis of cancer. This possibility has been investigated.

          

    Data from 6647 patients undergoing 131I therapy for hyperthyroidism was studied. 76% had an autonomously functioning node or a toxic multinodular goiter and 24% had Graves disease.

          

    After 131I therapy, only 0.15% showed evidence of cancer. None of those with Graves disease had cancer. 5 of the 10 patients with cancer had earlier been treated. This incidence was not different from that in the general population.        

                                                                                  

  • Gupta NC, Graeber GM, Bishop HA, (West Virginia Univ, Morgantown)

    Comparative Efficacy of Positron Emission Tomography With Fluorodeoxyglucose in Evaluation of Small (<1cm), Intermediate (1 to 3 cm), and Large (>3cm) Lymph Node Lesions            

    Chest 117: 773-778, 2000            

                                             

    The capability of FDG PET to aid in the detection of metastatic disease in lymph nodes of various sizes has been compared with that of CT.                                      

                                                                   

    118 patients with known or suspected non-small-cell lung cancer underwent CT and FDG PET studies. The results were compared with histological results from sampled lymph nodes of 54 patients.                  

                                                                 

    Of 118 patients, 79 had malignant primary lesions and 39 had benign lesions. Histologically there were 49 adenocarcinomas and 13 squamous cell carcinomas, 16 non-small-cell, 3 small cell, and 6 other carcinomas.               

                                                                           

    Of 168 lymph nodes sampled 53 were <1cm, 107 were 1-3 cm and 8 were >3cm in size. There were 53 malignant nodes.  

                                                                     

    Most lesions of <1cm were localized in the hilar/mediastinal nodes. The overall sensitivity, specificity, and accuracy of FDG PET and CT for staging mediastinal nodes were 96% and 80%, 93% and 95%, 94% and 92% respectively.           

                                                     

    The sensitivity, specificity, and accuracy for detecting lymph nodes <1cm, 1-3cm, and >3cm were 80%, 100%, and 100%; 95%, 91%, and 75%; and 92%, 95%, and 88% respectively.                             

                                              

    FDG PET results changed N staging in 25 patients and aided in the detection of disease in 15 of 17 lymph nodes missed by CT. 

                                                        

    FDG PET is more effective than CT for detecting metastatic disease in mediastinal lymph nodes.                    

                        

  • Yamamoto Y, Nishiyama Y, Satoh K, et al (Kagawa Med Univ, Japan)                      

    Comparative Evaluation of Tc-99m MIBI and TI-201 Chloride SPECT in Non-Small-Cell Lung Cancer Mediastinal Lymph Node Metastases                   

    Clin Nucl Med 25: 29-32, 2000                           

                                      

    Two nuclear medicine studies have been compared for use in assessing the mediastinal lymph nodes in non-small cell lung cancer: hexakis 2-methoxy isobutyl isonitrile (technetium 99m
    [99mTc] MIBI) and thallium 201 (201TI) chloride
    SPECT.   

                                     

    The study included 41 patients with non-small cell lung cancer (24 adenocarcinomas, 14 squamous cell carcinomas, 2 with adenosquamous cell carcinoma, and 1 with large cell carcinoma).               

                                    

    Simultaneous dual-isotope SPECT scanning with 201TI and
    99mTc-MIBI was done to evaluate mediastinal lymph node involvement, which was later confirmed by histopathology.               

                               

    32% had pathologically confirmed node involvement.                            

                                 

    Both early and delayed 99mTc-MIBI SPECT scan had a sensitivity of 69% and a specificity of 96% for detection of nodal metastasis.                              

                                              

    In comparison both early and delayed 201TI-chloride SPECT had a sensitivity of 92% with a specificity of 93% and 96% respectively.                                              

                                                   

    201TI SPECT scan is superior to 99mTc-MIBI SPECT for detection of mediastinal lymph node involvement.        

                   

  • Whiteford
    MH, Whiteford HM, Yee LF, et al (Washington Univ, St Louis)                                                            

    Usefulness of FDG-PET Scan in the Assessment of Suspected Metastatic or Recurrent Adenocarcinoma of the Colon and Rectum                                                                           

    Dis Colon Rectum 53: 759-770, 2000                                                                                 

                                                                                                                    

    The records of 105 patients who had had 101 CT and 109 FDG PET scans for suspected metastatic or recurrent colorectal adenocarcinoma were reviewed. The findings were confirmed at surgery by histopathology and by the clinical course.        

                                                                                                                               

    The overall sensitivity and specificity of FDG PET were 87% and 68% respectively in detecting clinically relevant tumor. For CT plus other conventional diagnostic studies these values were 66% and 59% respectively.                             

                                                                                                  

    The sensitivity of FDG PET was 58% for detecting mucinous cancer and 92% for non mucinous cancer.                          

                                                                                     

    For detecting locoregional recurrence the sensitivity of FDG PET and CT plus other conventional studies was 94% and 67% respectively.                                                                                        

                                                                                                         

    Compared with CT plus other conventional studies, FDG PET beneficially altered clinical management in 26% of cases.         

                                                                                 

  • Acland KM, O’Doherty MJ, Russell-Jones R (Guy’s and St Thomas’ Hosp, London)                               

    The Value of Positron Emission Tomography Scanning in the Detection of Subclinical Metastatic         
    Melanoma                            

    J Am Acad Dermatol 42: 606-611, 2000                 

                                                              


    Whole-body FDG-PET scans were performed after a 6-hour fast. The study group included those patients with primary cutaneous malignant melanoma in whom PET scanning revealed in-transit or regional spread to lymph nodes; as well as those patients known to have regional spread and in whom PET scans revealed distant metastases.                 

                                                                                                 

    False negative results were those with negative scans with positive histology. False positive results were those with suspect scan and negative histology or no subsequent progression
    of disease.                                               

                                                                                     

    The overall sensitivity of PET scanning was 78% with a specificity of 87%. On subset analyses with the M. D. Anderson staging system the sensitivity was 50% for stage I disease and 33% for stage II disease with specificities of 87% and 100% respectively. For stage II disease the sensitivity of PET scanning was 93% with a specificity of 50%. Restaging of the disease occurred in 35% of patients with true positive scans.                                                                  

                                                                                                  

  • Eigtved A, Andersson AP, DahlstrØm K, et al (Copenhagen
    Univ)                     

    Use of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in the Detection of Silent     
    Metastases from Malignant Melanoma                     
         

    Eur J Nucl Med 27: 70-75, 2000                                          

                                                                                

    The staging of malignant melanoma has been compared between fluorine 18
    (18F) FDG and by conventional methods.     

                                                                           

    38 patients (stage II/III) with malignant melanoma underwent PET imaging with
    18F-FDG and the results were compared with those of clinical examination and other imaging methods (CT, US, radiography, and liver function tests). Histologic data and findings of clinical follow-up were noted.                
                                       

                                                              

    A histologic diagnosis was possible in 29 of 38 patients (25 were malignant and 4 were benign). In the remaining 9 cases the patients refused biopsy or the location of the mass was unapproachable. The mean follow-up was 48 months (44-56 months).

                                                                    
                   

    With 18F-FDG PET, the sensitivity and specificity of foci overall were 97% and 56%, respectively compared with 62% and 22% respectively by routine methods. For intraabdominal foci sensitivity and specificity were 100% and 100% respectively, for both
    18F-FDG PET and routine methods.                                     

                                                                                

    The figures for pulmonary and intrathoracic foci were 100% and 33% respectively. Of patients evaluated 34% would not have their melanoma staged correctly by conventional methods alone.                                                 

                                                                                                    

    The discovery of disseminated disease can spare the patient from extensive mutilating surgery.
    18F-FDG PET should only be used along with a thorough clinical examination.                                                                     

                                                                               

  • Tyler DS, Onaitis M, Kherani A, et al (Duke
    Univ, Durham, NC)                                

    Positron Emission Tomography Scanning in Malignant Melanoma: Clinical Utility in Patients With Stage III Disease                         

    Cancer 89: 1019-1025, 2000           
                

                                              

    This is a prospective evaluation of PET in malignant melanoma.                       

                                                        

    The patients studied had clinically evident stage III disease in the form of palpable lymph node disease, in-transit disease, or both. In such cases, the sensitivity and specificity of PET could be measured and the limits of resolution better defined.    

                                           

    It would also be possible to determine how often PET identified unsuspected metastatic disease and how often these findings affected clinical management.                            

                                                  

    All 95 patients studied were considered for further surgery. Two independent observers assessed FDG PET activity independently and without knowledge of clinical or pathologic results. Of the 234 areas pathologically evaluated, 165 were confirmed to be malignant melanoma.                                     

                                                              

    The sensitivity of PET scanning, which identified 144 areas as positive was 87.3%. Included in the 21 missed areas of melanoma were 10 microscopic foci, 9 foci <1cm, and 2 foci >1cm.                                 

                                                          

    PET scan had a specificity of 43.5%, a negative predictive value of 58.8%, and a positive predictive value of 78.6%.          

                                                           

    13 of the 39 false positive areas could be attributed to recent surgery. Addition of clinical information improved the predictive value of a positive scan to 90.6%. 36 areas of increased PET activity represented unsuspected metastatic disease and the clinical management was changed in 15 of 95 patients.                      

                                                      

    PET scan is sensitive in the detection of metastatic disease in malignant melanoma, particularly unsuspected disease in stage III malignant melanoma. The abnormalities so detected can be further evaluated by a localized CT scan.    

              

  • Crippa F, Leutner M, et al (Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy)

    Which Kinds of Lymph Node Metastases Can FDG PET Detect? A Clinical Study in Melanoma

    J Nucl Med 41: 1491-1494, 2000

        

    The diagnostic accuracy of FDG PET for lymph node metastases has been evaluated and the smallest detectable volume of disease determined. 

                          

    56 lymph node basins in 38 patients were studied preoperatively with FDG PET. Patients studied had a clinical or instrumental diagnosis of lymph node metastases from melanoma. Subsequently all these areas were subjected to surgery. The results of FDG PET were compared with the post operative histopathology results. 

               

    The efficacy of FDG PET was good for the diagnosis of involved lymph node basins. It had a specificity of 84%, sensitivity of 95%, accuracy of 91%, a positive predictive value of 92% and a negative predictive value of 89%. 

         

    Histological evidence of metastases was seen in 114 of 647 surgically removed lymph nodes. FDG PET had a high sensitivity of
    >93%
    only for metastases with capsular infiltration or with greater than 50% involvement. Detection rate of FDG PET for metastases greater than 10 mm was 95%, the rate for metastases of 6-10 mm size was 83% and for metastases 5 mm or less in size the detection rate was 23%.  

                

    FDG PET has good sensitivity but false positive results are possible. 

                                        

  • Shah N, Hoskin P, et al (Mount Vernon Hosp, Northwood, England)     

    The Impact of FDG Positron Emission Tomography Imaging on the Management of Lymphomas    

    Br J Radiol 73: 482-487, 2000       

                         

    The role of FDG PET in the management of lymphomas has been assessed.      

                    

    29 patients undergoing FDG PET imaging during treatment of lymphoma have been reviewed retrospectively (12 Hodgkin’s and 17 non-Hodgkin’s lymphoma (NHL)).      

                                

    FDG PET imaging contributed additional information to clinical and CT findings in 41% of the patients with both positive and negative scans. There were 2 false positive FDG PET scans, reflecting FDG uptake in extranodal sites. The findings of FDG PET affected clinical management in 34% of the patients. In 2 patients the initial management was changed and in 8 consolidation therapy after completion of initial chemotherapy was altered.                 

                               

    Management changes were made for 6 patients with high grade NHL, 2 with low grade NHL and 2 with Hodgkin’s disease. 

                    

    This noninvasive modality enables evaluation of potential sites of active disease and compliments CT in the assessment of lymphoma.               

                                                                                             

  • Delcambre C, Reman O, et al (Centre Francois Baclesse, Caen, France; Centre Hospitalier Regionale Universitaire, Caen, France)                      

    Clinical Relevance of Gallium-67 Scintigraphy in Lymphoma Before and After Therapy    

    Eur J Nucl Med 27: 176-184, 2000     

                          

    The staging of lymphoma with 67Ga scintigraphy has been compared with staging with clinical assessment and conventional imaging (CI).           

                                                 

    62 patients were submitted to 67Ga scintigraphy (86 scans). 52 patients had Hodgkin’s lymphoma (HL) and 10 had non-Hodgkin’s lymphoma (NHL). In 44 patients it was done at diagnosis and in 42 patients after treatment. Examination was done with 185 to 220 MBq
    67Ga citrate and planar and SPECT studies. Assessment with CI consisted of plain X-ray chest, CT scan chest, abdomen and pelvis, abdominal US, lymphography, bone marrow biopsy, and when necessary MRI and bone scintigraphy.      

                                                

    For individual sites, before treatment there was complete agreement between the two methods in 57% of cases. More sites were demonstrated by clinical examination and CI than by scintigraphy in 27% and
    67Ga imaging showed more sites than CI in 11%.

                                  

    Clinical disease stage at scintigraphy only was in accordance with that which used all diagnostic procedures in 77% of cases. After treatment, CI and scintigraphic studies were normal in 11 patients all but one of whom remained in complete remission on a 31-month follow-up. 31 patients had a residual mass radiologically. Scintigraphy was normal in 71% of these patients.   

                              

    Scintigraphy demonstrated abnormal uptake in 9 of 31 patients with a large residual mass, 8 of whom had active disease and one with complete remission at 30-month follow-up.      

                                            

    67Ga imaging cannot replace CI in the diagnosis of lymphoma, but it may depict additional disease sites in more than 10% of cases, thus permitting clinical upstaging and better prognostication. After treatment it enables one to avoid unnecessary complementary therapy.       

                                                                     

  • Frohlich DEC, Chen JL, et al (Harvard Med School, Boston)

    When Is Hilar Uptake of 67Ga-Citrate Indicative of Residual Disease After CHOP Chemotherapy

    J Nucl Med 41: 269-274, 2000

                                   

    The patterns of Gallium hilar uptake (HU) after chemotherapy (CHOP) to treat NHL were analyzed including findings associated with hilar lymphoma (HL) versus benign
    HU.  

                          

    This prospective study included review of 930 67Ga-citrate scans, 698 planar and 232 thoracic SPECT from 100 patients with NHL (29 with low-grade disease, 60 with intermediate disease and 11 with high-grade disease). All patients had received CHOP therapy and were followed up for a mean of 36 months. The median number of planar gallium scans obtained during follow-up was 7.  

                                      

    The prevalence and patterns of HU were analyzed, including the relationship between HU and chemotherapy dose. Benign and malignant HU were differentiated based on clinical outcomes and changes over time on correlative CT scans or radiographs. 

                                        

    79% of patients had HU after CHOP including 33% with HU on SPECT scans alone. The median duration of persistent HU was 27% after onset. At baseline 52% had HU and 60% had HL. During CHOP therapy, 59% had HU but only 2% had HL. After CHOP therapy the figures were HU 52% and HL 6% respectively and HU 76% and HL 9% at follow-up.   

                                                       

    The presence of benign HU was not significantly related to chemotherapy dosage. In about 90% of patients, HU was symmetric and less intense then at baseline (correlated with benign HU). In contrast asymmetric HU of equal intensity to the original disease was strongly correlated with the presence of HL.    

                                   

  • Lapela M, Eigtved A, et al (Univ of Turku, Finland; Copenhagen Univ)

    Experience in Qualitative and Quantitative FDG PET in Follow-up of Patients With Suspected Recurrence From Head and Neck Cancer        

    Eur J Cancer 36: 858-867, 2000  

                    

    The value of FDG PET (a noninvasive method) in detecting recurrent head and neck cancer is investigated. 

                   

    62 FDG PET studies were obtained in 56 patients (a total of 81 lesions). All were clinically suspected of having recurrent head and neck carcinoma. The PET images were visually interpreted. Tracer uptake was quantitated as the standardized uptake value adjusted for body weight.   

                                

    Visual interpretation of the PET images for the presence of malignancy had a sensitivity between 84% to 95% and a specificity of 84% to 93% depending on the selected scheme for lesion grading.   

                                  

    Malignant lesions accumulated much more FDG than benign lesions. However FDG uptake values between these two groups overlapped greatly. Thus the most accurate quantitative analysis in recurrence detection was inferior to visual interpretation, these accuracies being 75% and 89%, respectively.             

                          

  • Stokkel
    MPM, Moons KGM, et al (Univ Hosp Utrecht, The Netherlands)

    18F-Fluorodeoxyglucose Dual-Head Positron Emission Tomography as a Procedure for Detecting Simultaneous Primary Tumors in Cases of Head and Neck Cancer

    Cancer 86: 2370-2377, 1999

                       

    This study compares the ability of 18F-fluorodeoxyglucose dual-head PET (FDG PET) with standard clinical tests in detecting secondary primary tumors. 

                                   

    This prospective study includes 68 patients with a primary tumor of the oral cavity or oropharynx. Each patient had a thorough clinical examination (excluding panendoscopy) before FDG PET was performed.    

                             

    Addiction to alcohol or smoking was documented and the patients were divided into groups on the basis of these habits. The follow-up period was at least 6 months with a view to identify synchronous tumors missed by FDG PET.    

                                 

    FDG PET detected secondary primary malignant tumors in 12 patients (18%). Only 5 of these tumors were detected by clinical or radiologic examination (7%). All but one of the tumors detected by FDG PET were located in the epithelium of the upper digestive tract/respiratory tract. None of these patients had simultaneous or synchronous primary tumors during the follow-up period.             

                                                              

    FDG PET is an attractive option in the assessment of patients with head and neck cancer.          

       

  • Boerner AR, Weckesser M, et al (Univ Hosp Dusseldorf, Germany; Research Centre Julich, Germany, et al)

    Optimal Scan Time for Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Breast Cancer 

    Eur J Nucl Med 26: 226-230, 1999

           

    A 3-hour imaging protocol was performed in women with primary breast cancer to determine whether this approach would improve tumor detectability and image contrast. 

          

    29 women with tumors of 2 cm or greater in diameter found to be malignant by biopsy were studied. 370 to 740 Mbq fluorine 18-FDG and scanned in the prone position. Data were obtained at 0 to 40 minutes, 1.5 hours and 3 hours after injection. 

          

    Tumor to nontumor and tumor to organ ratios were significantly greater for the images obtained at 3 hours than for those obtained at 1.5 hours. Lesion detectabilities at 1.5 and 3 hours were 83% and 93% respectively.

            

    Obtaining the scan at 3 hours appears to increase the diagnostic sensitivity of FDG PET.   

                                                                

  • Yutani K, Shiba E, et al (Kaizuka City Hosp, Japan; Osaka Univ, Japan)  

    Comparison of FDG-PET with MIBI-SPECT in the Detection of Breast Cancer and Axillary Lymph Node Metastasis      

    J Comput Assist Tomogr 24: 274-280, 2000            

                                        

    This is a comparative study of two non invasive techniques, FDG-PET and
    99mTc-methoxyisobutylisonitrile (MIBI-SPECT) in the detection of breast cancer and axillary lymph node metastases in the same patients.  

                                                    

    40 women (25-86 years) with suspected breast cancer and in whom biopsies or mastectomies were performed underwent both FDG-PET and MIBI-SPECT within 3 days. The images were assessed visually and calculation of count ratio between tumor and normal (T/N ratio) tissue was performed.               

                                                             

    38 cancers and 2 benign breast lesions were detected. For breast cancer the sensitivity of FDG-PET was 78.9% and that of MIBI-SPECT was 76.3%. For axillary lymph node metastases the sensitivity of FDG-PET was 50% and that of MIBI-SPECT was 37.5%. FDG-PET demonstrated a significantly higher T/N ratio of breast cancer that was seen with MIBI-SPECT. Tumor uptake was obscured occasionally by non-malignant diffuse uptake of FDG in the breast and accumulation of MIBI in the heart and liver.           

                                                                                        

    Both FDG-PET and MIBI-SPECT have comparable capabilities in the detection of breast carcinoma. However, neither modality has enough sensitivity to rule out axillary lymph node metastases.             

                                                                            

  • Obwegeser R, Berghammer P, et al (Univ of Vienna)            

    A Head-to-Head Comparison Between Technetium-99m-Tetrofosmin and Technetium-99m-MIBI   
    Scintigraphy to Evaluate Suspicious Breast Lesions           

    Eur J Nucl Med 26: 1553-1559, 1999                

                                                                                                         

    The diagnostic value of 99m (99m
    Tc)-tetrofosmin and 99mTc-MIBI have been compared to evaluate suspicious breast cancer.

                                                

    The 2 radiopharmaceutical agents were administered randomly on different days in 101 women (103 breast tumors) in a prospective open diagnostic trial. Planar images and SPECT scans were obtained and tumors were subjected to histopathology.

                                                          

    The sensitivity of 99mTc-tetrofosmin and 99mTc-MIBI was only 44% and 46% respectively for planar images. For SPECT sensitivity was improved to 70% and 69% respectively. Specificity for planar images was 83% and 87% and for SPECT 70% and 78% respectively. The positive predictive value was 76% and 81% respectively for planar images and values were comparable for SPECT. The negative-predictive values were 54% and 57% for planar images and 65% and 67% respectively for SPECT. 

                                                                   

    The 2 agents have similar diagnostic value. SPECT improves sensitivity but not specificity. It however provides additional information about tumor location.               

                                                                                                                                                                                     

  • Rostom AY, Powe J, et al (King Khalid Univ, Saudi Arabia)

    Positron Emission Tomography in Breast Cancer: A Clinicopathological Correlation of Results

    Br J Radiol 72: 1064-1068, 1999          

                          

    The diagnostic value of PET in patients with primary, recurrent or metastatic breast disease (cancer) was evaluated. 

                                     

    109 selected breast cancer patients who underwent FDG-PET (whole body) were included in this study. In addition all patients underwent bone scans, liver ultrasonography (US) or abdominal CT plus chest CT or radiography and 86 patients underwent mammography. Histological data was available in 105 patients. 

                       

    The sensitivity, specificity and accuracy of PET imaging of the primary tumor and lymph nodes were evaluated. For patients with metastases, the accuracy of PET, was compared with that of other imaging modalities. 

                         

    For tumor evaluation PET had an accuracy of 89% with a false positive rate of 3% and false negative rate of 8%. Accuracy was 91% for lymph node evaluation with a false negative rate of 10%.

                       

    PET had an accuracy of 90% versus 72% for mammography (86 patients) for primary tumor. PET findings in 19 patients with metastases agreed with those of other imaging studies.                       

                                                                                                           

    PET can be used for diagnosis staging and evaluation of therapy response in cases of breast cancer.           

                                                                                           

  • Ortapamuk H, Ozmen MM, et al (Ankara Numune Hosp, Turkey)

    Role of Technetium Tetrofosmin Scintimammography in the Diagnosis of Malignant Breast Masses and Axillary Lymph Node Involvement: A Comparative Study With Mammography and Histopathology

    Eur J Surg 165: 1147-1153, 1999

                                                     

    The role of technetium 99m (99mTc) tetrofosmin scintimammography has been examined in the detection of breast cancer and axillary lymph node metastases. 

                                        

    128 women with breast masses underwent clinical examination and standard mammogram. Scintigram (mammography) was performed within 1 week of mammography for women with palpable masses or mammographic evidence of abnormalities or both. The final diagnosis was determined by excision biopsy. 

                                                 

    The contol group (30 women) with no palpable mass who had been referred for myocardial perfusion scintigraphy. The sensitivity, specificity and positive and negative predictive values of scintimammography were compared with those of mammography.

                                

    Of 80 scintimammography positive lesions, 78 were malignant and 2 benign. Of 48 scintimammography negative lesions, 44 were benign and 4 were malignant. 

                                                     

    For 99mTc scintimammography, the sensitivity, specificity and positive and negative predictive values were 95%, 96%, 97% and 92% respectively. For standard mammography, these values were 87%, 26%, 68% and 52% respectively. 34 false positive mammograms were changed into true negative findings with scintimammography, at the expense of 4 false negative results. The sensitivity and specificity of scintimammography for axillary lymph node metastases were 72% and 100% respectively.



    99mTc-tetrofosmin scintigraphy is helpful in the detection of breast cancer and axillary nodal metastases. It may help prevent unnecessary surgery in doubtful cases.                         

                                                                                

  • Jansen L, Doting MHE, et al (The Netherlands Cancer Inst, Amsterdam; Groningen Univ, The Netherlands)

    Clinical Relevance of Sentinel Lymph Nodes Outside the Axilla in Patients with Breast Cancer

    Br J Surg 87: 920-925, 2000

                                  

    Patients with early stage breast cancer were examined to characterize the incidence of sentinel lymph nodes (SLNs) outside of the axilla, their identification and the clinical relevance. 

                                        

    113 women (mean age 58 years) with T1-3,
    N0, M0 breast cancer were studied. SLNs were identified by blue staining and gamma probe. All SLNs were examined histopathologically and by immunohistochemistry. Of special interest were SLNs outside the area of a level I-II axillary dissection. Regardless of SLN status all patients underwent level I-III axillary dissection.

                        

    SLNs outside the axilla were common (21 patients i.e. 19%). Most of these patients (18 or 86%) had SLNs both in the axilla and at another site. However in 3 patients (14%) the only SLN identified were outside the axilla. Of the 30 SLNs outside the axilla, 22 (73%) were harvested (more difficult than SLNs in the axilla). 

                               

    Of the 21 patients with SLNs outside the axilla, 8 had regional metastases. 4 of them had no metastases outside the axilla and 1 had metastases in SLNs in the interpectoral fossa and at level I of the axilla. 

                                 

    Therefore, biopsy of the SLNs outside the axilla did not change staging and postoperative treatment in these 5 patients. In the remaining 3 patients tumor positive SLNs were found in the internal mammary chain and these patients were upstaged to
    pT1N3 (2 patients) and pT3N3 (1 patient).                          

                     

    These latter 3 patients received radiotherapy to the internal mammary chain based on SLNs outside the axilla. None of the patients experienced complications as a result of SLN harvesting. 

                              

    SLN harvesting was technically difficult, but did not increase the morbidity. Biopsy of SLNs outside the axilla changed staging and treatment in only 3 patients (2.5%).                      

                                               

  • Kabasakal L, Halac M, et al (Cerrahpasa Med Faculty, Istanbul, Turkey)

    The Effect of P-Glycoprotein Function Inhibition With Cyclosporine A on the Biodistribution of Tc-99m Sestamibi           

    Clin Nucl Med 25: 20-23, 2000            

                                                     

    Verapamil and cyclosporine are 2 drugs that can partially or completely reverse drug resistance and restore sensitivity of cytotoxic agents by inhibiting P-glycoprotein transport function. The effect of cyclosporine on the biologic distribution of
    99mTc sestamibi was examined in vivo in 5 patients with alopecia and 2 patients who underwent renal transplantation and were treated with
    cyclosporine.              

                                                  

    All 7 patients were evaluated before and at 2 weeks after receiving cyclosporine. Patients underwent
    99mTc sestamibi scintigraphy. Planar abdominal images were taken at 5, 30, 60, 120 and 180 minutes after injection and after determination of liver-heart ratios. All patients underwent evaluation of plasma cyclosporine, bilirubin levels, liver enzymes and creatinine levels.

                                                  

    The plasma cyclosporine levels were increased to 400 pg/dL in 3 patients, and the liver-heart ratio rose significantly after cyclosporine administration. There was a delay in
    99mTc sestamibi excretion and liver uptake rose after cyclosporine administration. Differences were 17% and 38%, respectively, at 5 and 180 minutes.

                                                  

    The highest liver retention was observed in patients with cyclosporine toxicity. Inhibition of P-glycoprotein transport delyas liver excretion and enhances liver uptake of
    99mTc sestamibi.      

                                                                                           

  • Watanabe H, Shinozaki T, et al (Gunma Univ, Japan; Toho Hosp, Gunma, Japan)

    Glucose Metabolic Analysis of Musculoskeletal Tumours Using
    18Fluorine-FDG PET as an Aid to Preoperative Planning                 

    J Bone Joint Surg Br 82-B: 760-767, 2000                   

                                                                   

    Tumor tissue generally displays enhanced glycolysis and hence 18-FDG has been used as an imaging agent in conjunction with PET not only to evaluate primary brain tumors but also to distinguish between other lesions such as pancreatic carcinoma and mass forming pancreatitis.                        

                                                                                                 

    The standardized uptake value (SUV) can be used as a prognostic factor for pancreatic carcinoma when calculated with FDG-PET. Scanning with FDG was performed on patients with tumors involving the musculoskeletal system to evaluate the role of FDG-PET in operative planning.                     

                                                                                 

    FDG-PET scanning was performed in 55 patients (26 M, 29 F, mean age of 45.3 years). All the patients were suspected to have bone or soft tissue tumors. After calculation of the SUV of FDG, the patients were divided into high SUV (>1.9) and low (<1.9) groups to distinguish malignant from benign lesions.                    

                                                      

    The sensitivity of PET was 100% for diagnosis of malignancy with a specificity of 76.9% and an overall accuracy of 83%. The mean SUV for metastatic lesions was twice the mean SUV for primary sarcomas.         

                                                                     

    SUV has a role in the differentiation of malignant from benign lesions. However some benign lesions such as schwannomas had high SUVs and thus histopathology of the lesion is important.                      

                                                                 

    Reverse transcription polymerase chain reaction analysis demonstrated that the RNA message of phosphohexose isomerase (PHI/autocrine motility factor, a critical enzyme in glucose metabolism was augmented in high FDG-uptake lesions, but not low FDG uptake lesions.                         

                                                                                                          

    This suggests that there may be an association between the high expression of the PHI message and accumulation of FDG in musculoskeletal tumors.                   

                                                                                                                                                                                            

  • Schwarzbach
    MHM, Willeke F, et al (Univ of Heidelberg, Germany; German Cancer Research Ctr, Heidelberg, Germany)

    Clinical Value of [18-F] Fluorodeoxyglucose Positron Emission Tomography Imaging in Soft Tissue Sarcomas                  

    Ann Surg 231: 380-386, 2000       

                                                             

    The use of FDG-PET for evaluation of suspected soft tissue sarcomas, including noninvasive tumor grading, identification of viable tumor tissue, and posttreatment follow-up, has been studied.    

                                                                  

    The analysis includes prospectively collected data on 59 suspected primary or recurrent soft tissue sarcomas in 50 patients. The uptake of FDG was evaluated qualitatively and quantitatively with standardized uptake values (SUVs) calculated in tumor and in normal muscle tissue. The FDG-PET findings were correlated with surgical and follow-up data.       

                                            

    FDG-PET had a sensitivity of 91% and specificity of 88% in the detection of primary soft tissue sarcomas. For local recurrences, sensitivity was 88% and specificity 92%. All intermediate and high-grade sarcomas (primary and locally recurrent) were accurately visualized and differentiated from control muscle tissue.     

                                                 

    However, in half of the low-grade sarcomas, FDG uptake was equal to that of normal muscle. No FDG accumulation was seen in benign soft tissue tumors, but it did accumulate in inflammation. Although FDG SUVs were significantly correlated in with sarcoma grade, they did not reflect the tumor size or histology.   

                                                                                                    

    FDG-PET has promise as a complementary preoperative imaging study for soft tissue sarcomas.

       

  • Durand E, Prigent A (Hopitaux de Paris)

    Can Dimercaptosuccinic Acid Renal Scintigraphy Be Used to Assess Global Renal Function?

    Eur J Nucl Med 27: 727-730, 2000

      

    The goal of this study is to determine whether renal absolute DMSA uptake can reflect the absolute renal function.

    A simple monoexponential model was used to complete the absolute DMSA uptake in the event of injury to one kidney.

    The results of this experiment indicate that the assumption that absolute DMSA uptake accurately reflects absolute renal function may lead to more than a 50% overestimation of the function of both the normal and impaired kidney.

    It was also found that the error becomes increasingly important the later the measurement is made and the more impaired the kidney is at the time.

    DMSA can provide reliable quantification of relative renal function, but it should not be used in the assessment of absolute renal function because significant overestimation is possible.

        

  • Pusuwan P, Reyes L, et al (Great Ormond Street Hospital for Children, NHS Trust, London)

    Normal Appearances of Technetium 99 Dimercaptosuccinic Acid in Children on Planar Imaging

    Eur J Nucl Med 26: 483-488, 1999

      

    The appearances of 99mTc DMSA images of children with normal kidneys on renal arteriography were analyzed.

      

    32 children undergoing renal arteriography with normal results also underwent DMSA imaging. The criteria for high quality 99mTc DMSA imaging were based on kidney outline and contrast between the inner and outer part of the kidney. Most images were of high quality. The most common feature was a round or flat contour present in 50% and 24.8% respectively. The were a small number of unusual appearances. The mean differential function of the left kidney was 51% (45%-57%).

       

  • Peng N-J, Kwok CG, et al (Veterans gen Hosp, Kaohsiung, Republic of China; Veterans Gen Hosp, Taipei, Republic of China; et al)

    Posterior 1800 99mTc-Dimercaptosuccinic Acid Renal SPECT

    J Nucl Med 40: 60-63, 1999

      

    The quality of renal SPECT images can be attenuated by the liver and spleen. This study evaluates whether 1800 SPECT improves image quality over that obtained with a 3600 imaging technique.

      

    Out of 134 patients culled, 2 groups were formed. Group 1 (41 patients) had a normal 99mTc DMSA planar and SPECT image results together with normal blood chemistry results; in group 2 (16 patients) definite cortical defects were visible on planar and SPECT images.

    A anterior 1800, posterior 1800 and 3600 renal SPECT images were obtained. Total data counts, with regions of interest highlighted on coronal and reoriented saggital slices and quantitative assessment of regional activity were made.

      

    Group 1 patients had obvious organ attenuation on the 3600 scans. The total data counts from the posterior 1800 view exceeded those of the anterior 1800 view. The posterior images were more homogenous than either of the other, as also a significantly greater upper to lower pole ratio. In group 2 patients renal defects were seen more clearly on the posterior 1800 SPECT images; the anterior 1800 images gave the worst view.

      

    Only half of the data were provided by the posterior 1800 method, but more uniform appearing kidneys and higher lesion contrast was obtained. The problem of hypoactive poles could also be avoided by using this technique.

        

  • Craig
    JC, Wheeler DM, et al (The New Children’s Hosp, Sydney, Australia; Univ of Sydney, Australia)

    How Accurate Is Dimercaptosuccinic Acid Scintigraphy for the Diagnosis of Acute Pyelonephrits? A Meta-analysis of Experimental Studies

    J Nucl Med 41: 986-993, 2000

      

    Renal tract imaging with 99mTc DMSA scintigraphy has largely replaced IV urography as a test for assessing renal parenchymal damage from urinary tract infection in children. The role of DMSA scintigraphy has been investigated in the diagnosis of acute pyelonephritis. The standard technique, planar DMSA was compared with SPECT
    DMSA.

      

    Animal studies comparing DMSA scintigraphy with histopathology were reviewed. Of 7 studies, 2 included SPECT DMSA. Problems in study design and reporting were common. Numerical errors were found in 4 studies. Overall SPECT DMSA had an estimated specificity of 91% at a sensitivity of 86%. The threshold for detecting acute pyelonephritis was lower for SPECT than for planar
    DMSA.

      

    Applied to a hypothetical group of 100 children with a 40% prevalence of renal damage, 98% of the children with abnormal planar DMSA scans would have renal damage, whereas only 65% of those with abnormal SPECT scans would have renal damage.

      

    Planar and SPECT DMSA would miss 11% and 3% respectively of children with renal damage. In this hypothetical group SPECT would identify 6 additional true cases of renal damage but yield 19 additional false positive results compared with planar DMSA. SPECT DMSA alone does not appear to be preferable to the established planar
    DMSA.

       

  • Sattari A, Kampouridis S, et al (Hopital Universitaire Saint-Pierre Bruxelles Belgium; Hopital Universitaire des Enfants de la Reine Fabiola, Bruxelles, Belgium)

    CT and 99mTc DMSA Scintigraphy in Adult Acute Pyelonephritis: A Comparative Study

    J Comput Assist Tomogr 24: 600-604, 2000

      

    The role of CT and 99mTc DMSA scintigraphy in the diagnosis of APN (acute pyelonephritis) in adults thought to have urinary tract infection (UTI) have been investigated.

     

    36 patients with UTI underwent plain B-mode sonography, CT scan with contrast and 99mTC DMSA scintigraphy of the kidneys. The latter two were performed within 72 hours after admission.

     

    In 12 patients with clinical and biological signs of UTI, both CT and DMSA scintigraphy were normal. In this group 10 patients had lower UTI and 2 had ureteral obstruction. In the remaining 24 patients APN was diagnosed. In 11 of these patients CT and 99mTc DMSA scintigraphy were correlated.

      

    Findings on both examinations were normal in 2 patients and abnormal in 9. In the remaining 13 patients, 11 had abnormal CT findings but normal scintigraphic findings and 2 had normal CT but abnormal scintigraphic findings.

      

    In 2 patients bilateral lesions detected by CT appeared as unilateral abnormalities on 99mTc DMSA scintigraphy in diagnosing APN lesions.

       

  • Yen T-C, Tzen K-Y, et al (Chang Gung Univ, Taipei, Taiwan; Natl Yang-Ming Univ, Taipei, Taiwan)

    The Value of Ga-67 Renal SPECT in Diagnosing and Monitoring Complete and Incomplete Treatment in Children with Acute Pyelonephritis

    Clin Nucl Med 24: 669-673, 1999

       

    The usefulness if 67Ga Renal SPECT in the diagnosis and monitoring of children with acute pyelonephritis (APN) has been evaluated.

       

    71 children with suspected APN (1 week to 12 years) underwent Renal SPECT scanning within 3 days of hospital admission 99mTc DMSA and 67Ga renal SPECT cystourethrography were done and repeated 3 months after treatment for those with abnormal initial findings.

      

    Lesions were detected on 97% of the 67Ga and 79% of the 99mTc DMSA renal SPECT images. 67Ga renal SPECT also returned 3 false negative results. 17 patients who were positive by the 67Ga SPECT were negative on 99mTc DMSA. 30% of the 107 kidneys had permanent scars, 78% of those were associated with high grade vesicoureteral reflux and 27% with low grade or no vesicoureteral reflux. Posttherapy imaging did not detect 67Ga uptake in any patients.

      

    67Ga renal SPECT presents a more effective diagnosis of APN and enhanced monitoring abilities when compared with 99mTc DMSA renal SPECT. It may also prove more accurate in detecting the extent of vesicoureteral reflux in patients with
    APN.

        

  • Chan Y-L, Chan K-W, et al (Chinese Univ of Hong Kong, China)

    Potential Utility of MRI in the Evaluation of Children at Risk of Renal Scarring

    Pediatr Radiol 29: 856-862, 1999

      

    The use of MRI in children at risk for renal scarring was assessed by comparing it to technetium 99m-dimercaptosuccinic acid (99mTc-DMSA).

      

    24 children at increased risk for urinary tract infection (UTI) because of spinal dysraphism and neurogenic bladder or anorectal anomaly (18 and 6 children respectively) were assessed. None of them had a history of acute
    pyelonephritis.

      

    The mean age of the 11 girls and 3 boys was 5.3 years. 10 children had documented UTI and 14 had a history of asymptomatic bacteraemia. Patients underwent 99mTc-DMSA scans and MRI to assess renal scarring. The 99mTc-DMSA scans were supplemented with pin hole imaging. The MRI of the kidneys used a fat saturated T1-weighted sequence and the post-gadolinium STIR sequence used a short echo time.

      

    16 kidneys (33%) showed a renal parenchymal defect indicative of scarring on 99mTc-DMSA. The concordance in detection of a scarred kidney by post-gadolinium STIR sequence and 99mTc-DMSA fat saturated T1-weighted sequence and 99mTc-DMSA and both sequences respectively, had a sensitivity of 94%, 82%, and 100%. With 99mTc-DMSA as the gold standard MRI had a sensitivity and specificity of 100% and 78% respectively, in the diagnosis of a scarred kidney.

      

    Concordance in detection of a scarred zone by post-gadolinium STIR sequence and 99mTc-DMSA fat saturated T1-weighted sequence and DMSA, and both sequences respectively had a sensitivity of 68%, 44% and 84% respectively. With 99mTc-DMSA as the gold standard, the sensitivity and specificity of MRI in the detection of a scarred zone was 84% and 86%
    respectively.

      

  • Wong DC, Rossleigh MA, et al (Prince of Wales and Sydney Children’s Hosp, Australia)

    Diuretic Renography With the Addition of Quantitative Gravity-Assisted Drainage in Infants and Children

    J Nucl Med 41: 1030-1036, 2000

       

    The use of quantitative gravity assisted drainage using greater than 50% residual activity as an indicator to verify obstruction in diuretic renography in the investigation of hydronephrosis and hydroureteronephrosis in infants and children has been evaluated.

      

    200 children (aged 2 days to 16 years) were studied. In 135 patients diuretic was given 20 minutes after radiopharmaceutical, and in 65 patients, the two were administered simultaneously.

      

    Studies were done with IV administration of technetium 99m-mercaptoacetyltriglycine (99mTc-MAG3) and furosemide. A 5-minute post- gravity-assisted drainage image was obtained after 20 minute diuretic phase. The percentage of residual activity was calculated by comparison with the last 5 minutes of the diuretic phase. All patients were monitored for 6-12 months. The final diagnoses was based on surgical findings or conservative management with follow-up sonography or 99mTc-MAG3 studies.

      

    10 of 256 hydronephrotic renal units showed no function and 1 showed poor function. 131 units had a half life (t1/2) of <10 minutes; 52 units had a half life of 10-20 minutes and 62 units >20 minutes.

       

    Only 1 case of obstruction was found among 131 renal units (t1/2 <10 minutes). Based on gravity assisted drainage exceeding 50% residual activity for diagnosing obstruction in 62 renal units (t1/2 >20 minutes). The sensitivity was 88.4% the specificity 73.7% and the accuracy 83.9%. By using gravity assisted drainage exceeding 50% residual activity for diagnosing obstruction in 52 units with t1/2 of 10-20 minutes, the sensitivity was 100%, the specificity 79.5% and the accuracy of 82.7%.

       

    This test can distinguish between obstruction and non-obstruction in renal units with t1/2 >20 minutes only.

         

  • Clorius JH, Schottler T, et al (Univ of Heidelberg, Germany)

    Afferent-Efferent Vessel Dysfunction Appears to Be a Specific Characteristic of a Large Subset of Patients with Essential Hypertension

    Am J Hypertens 13: 332-339, 2000

        

    Exercise renography distinguishes between exercise mediated renal dysfunction (50%-60%) and non exercise mediated dysfunction. This study aims to find out whether disturbances are also present at rest.

       

    26 patients with essential hypertension (EH) and 21 normotensive persons were assessed with a resting sequential renogram by using technetium 99m (99mTc) mercaptoacetyltriglycine (MAG3). Patients with EH also underwent exercise renography. 3 consecutive 10 minute dual-tracer infusion clearance determinations were made with indium 111-DTA and iodine 131-hippurate to simultaneously determine glomerular filtration rate (GFR) and effective renal plasma flow.

       

    Exercise mediated renal dysfunction developed in 16 of 26 cases of EH. The variability of GFR differed between patients and control subjects. The variability fraction indicated that patients with a bilateral abnormal exercise renogram had a more marked GFR variability than those patients with a normal exercise
    renogram.

       

    Intraglomerular pressure fluctuations appear to be present in patients with EH. The variable GFR may provoke renin secretion in EH.

       

  • Van de Ven PJG, de Klerk JMH, et al (Univ Med Ctr Utrecht, The Netherlands)

    Aspirin Renography and Captopril Renography in the Diagnosis of Renal Artery Stenosis

    J Nucl Med 41: 1337-1342, 2000

       

    This study compares aspirin versus captopril renography for diagnosis of renal artery stenosis (RAS).

      

    Aspirin and captopril renography were compared prospectively with technetium 99m mercaptoacetyltriglycine (99mTc-MAG3) in 75 consecutive patients suspected of having RAS. Intraarterial digital subtraction angiography was performed on all patients within a month of the last renographic study (50% or more reduction in renal artery diameter was considered positive for RAS).

      

    RAS was identified unilaterally in 34 patients and bilaterally in 17. 24 patients had no evidence of RAS. The sensitivity of captopril renography was 88% for both unilateral and bilateral RAS. For aspirin renography, the sensitivities for unilateral and bilateral RAS were 82% and 94%
    respectively.

       

    The overall specificity for RAS was 75% for captopril renography and 83% for aspirin renography. There was no significant difference between the two methods in tracer uptake ratios, time to peak activity and percentage of 20 minute tracer retention.

       

    In subgroup analysis of modest and severe RAS and of plasma creatinine >120 mmol/L, no differences were seen. The two methods are almost equal in the diagnosis of RAS.

        

  • Juillard L, Janier MF, et al (Hopital Edouard Herriot, Lyon, France; Hopital Cardiologique, Bron, France; et al)

    Renal Blood Flow Measurement by Positron Emission Tomography Using 15O-Labeled Water

    Kidney Int 57: 2511-2518, 2000

       

    A non-invasive method of determining renal blood flow (RBF) would be valuable. PET with oxygen 15-labeled water (H215O) could be used to non invasively measure RBF. An animal model has been used to validate the measurement of RBF by PET with H215O.

      

    The study was performed on 6 four month old farm pigs. RBI was assessed for each pig with both PET and radioactive microspheres (MS) at baseline during continuous dopamine infusion associated with vascular expansion by hydroxyethyl starch (HES) and isotomic saline and during continuous angiotensin II infusion.

      

    PET and MS were highly correlated over RBF range from 100 to 500 mL/min per gram. Pharmacologically induced changes were assessed equally well by PET and MS.

      

    PET with H215O appears to be a useful non-invasive technique for the measurement of RBF. The limitations are the cost and the PET availability. Benefits include possibility of rapid sequential measurements, comparison between measurements and reduced irradiation.

       

  • Isiklar I, Aktas A, et al (Baskent Univ, Ankara, Turkey)

    From Donor to Recipient: Doppler US, Power US and Scintigraphy of Kidney Perfusion Before and After Transplantation

    Acta Radiol 41: 285-287, 2000

       

    Duplex Doppler US, Power Doppler US and Scintigraphy have been prospectively used to examine kidney perfusion before and after donation to study the changes in perfusion status.

      

    12 donor/recipient pairs were studied. Both kidney donors were studied before surgery with duplex Doppler US, power Doppler US and scintigraphy. Renal allografts were assessed 1 day, 1 month and 3 months postoperatively. Multiple resistance indices were calculated, based on interlobar and segmental artery flow. All patients in the study group had normal kidney function.

      

    In the normally functioning kidneys postoperatively after 1 month, the intrarenal resistance and after 3 months there was a decrease in renal artery peak systolic velocity.

        

  • Russell CD, Yang H, et al (Univ of Alabama, Birmingham; Shanxi Med Univ, Taiyuan, China)

    Prediction of Renal Transplant Survival From Early Postoperative Radioisotope Studies

    J Nucl Med 41: 1332-1336, 2000

      

    A 3-day postoperative (renal transplant) study is usually performed – imaging, estimation of effective plasma renal flow (ERPF) from a simple plasma sample. The co-relation between baseline measurements and 1-year graft survival have been presented.

       

    In 1998 iodine 131-orthoiodohippurate (OIH) was used and in 1995 technetium-99m-mercaptoacetylglycine (99mTc-MAG3) was used. Previously published single injection single sample methods were used in the concurrent measurement of ERPF and gamma camera imaging by converting MAG3 clearance to ERPF by means of a correction factor.

      

    Graft survival in the first postoperative year was significantly improved in the interval between the cohort years (1988 and 1995) from 74% of 146 cadaver grafts in 1988 to 91% of 200 cadaver grafts in 1995.

      

    However there was no significant change for living related donors (LRD) grafts which were successful for 91% of 66 (1988) and 91% of 83 (1995). In both cohort years the baseline ERPF was a significant predictor of graft survival. The association was not significant for LRD grafts in either cohort. In the 1995 cohort, the peak time and ratio of counting rate at 20 minutes to that at 3 minutes (R20:3) were also found to be significant predictors for cadaver graft survival.

       

    In the 1988 cohort the correlation with peak time was not significant, and the 

    the R20:3 measurement was not available. Simple sample ERPF in the immediate post transplant period whether from OIH clearance or MAG3 clearance is a significant predictor of graft survival for cadaver transplants. Peak time and R20:3 were also found to be significant predictors for MAG3. However these associations are not valid for LRD transplants.

        

 



 

 

Speciality Spotlight

 

 
Nuclear Medicine
 

 

  • Ramos CD, Zantut-Wittmann DE, Tambascia MA, et al (Campinas State Univ, Brazil)
    Thyroid Suppression Test With L-Thyroxine and [99 mTc] Pertechnetate
    Clin Endocrinol (Oxf) 52: 471-477, 2000
          
    This article evaluates the efficacy of L-thyroxine as a TSH suppressor and technetium 99m (99mTc) pertechnetate as a radiopharmaceutical agent for diagnosing autonomous functioning thyroid nodules.
        
    15 healthy volunteers (21-35 years) and 20 patients (27-83 years) were studied (7 autonomic functioning non-toxic nodules, 3 autonomic functioning toxic nodules, 7 with Graves’ disease and 3 with non- autoimmune diffuse toxic goiter). Baseline thyroid uptake and imaging were done 20 minutes after an IV injection of 370 MBq of 99mTc pertechnetate, followed by a single daily dose of L-thyroxine (2 mg/kg) for 10 days. At this time, thyroid uptake and imaging were repeated.
        
    The mean reduction in 99mTc pertechnetate uptake after L-thyroxine suppression was 75.8% from baseline in the control group. All subjects were euthyroid, and there were no adverse effects. The uptake declined by 39% in 10 patients, was unchanged in 2 and increased in 8.
         
    This method effectively demonstrates autonomous thyroid tissue. It is as effective as the original T3 suppression test, but is more convenient because of ease of hormonal intake, low dosimetry and short stay. There are no adverse effects.
          

  • Erdil TY, Onsel C, Kanmaz B, et al (Marmara Univ, Istanbul, Turkey; Istanbul Univ, Turkey; Hacettepe Univ, Ankara, Turkey)
    Comparison of 99mTc-Methoxyisobutyl Isonitrile and 201TI Scintigraphy in Visualization of Suppressed Thyroid Tissue
    J Nucl Med 41: 1163-1167, 2000
          
    201TI (thallium) and MIBI (methoxyisobutyl isonitrile) have been compared in the visualization of suppressed thyroid tissue in patients with a solitary toxic autonomously functioning thyroid nodule (AFTN).
           
    32 patients with toxic AFTNs seen on 99mTc pertechnetate screening underwent MIBI and 201TI scanning within 3 days. Scintigrams were analyzed semiquantitatively as well as visually. In the semiquantitative analysis, regions of interest (ROIs) were produced over the nodule (N) and contralateral normal lobe (E) and the mean ROI counts were made.
         
    The mean N/E uptakes were 11.37 for partechnate and 4.76 for MIBI and 1.63 for 201TI in triiodothyronine (T3) plus thyroxine (T4) hyperthyroid patients.
          
    In T3 hyperthyroid patients these values were 9.46, 2.73 and 1.57 respectively. 201TI uptake of suppressed thyroid tissue compared with AFTN was more marked and significantly higher than that of MIBI for both groups.
         
    When the N/E uptakes of the two groups were compared neither pertechnate nor 201TI differed significantly. However, the N/E uptake of MIBI in T3 + T4 hyperthyroid patients was significantly greater than in the T3 group.
         
    201TI is better than MIBI in visualizing suppressed thyroid tissue in patients with a toxic thyroid nodule. An increased metabolic rate in the follicular cells of AFTNs in T3 + T4 hyperthyroid patients compared with that in T3 hyperthyroid patients may be responsible for the greater N/E for MIBI compared with that of 201TI.
          

  • Reschini E, Matheoud R, Canzi C, et al (Ospedale Maggioreo, Milano, Italy; Ospedale Fatebenefratelli, Milano, Italy; Ospedale S Pio X, Milano, Italy; et al)
    Dosimetry Study in Patients With Autonomous Thyroid Nodule Who Are Candidates for Radioiodine Therapy
    J Nucl Med 40: 1928-1934, 1999
         
    Autonomous thyroid nodules are treated successfully with radioiodine therapy. The development of hypothyroidism after such therapy may be related to extranodular dosing.
          
    17 patients with elevated free thyroxine or free triiodothyronine levels and 9 patients with normal levels were studied. Radioiodine turnover parameters were determined for the nodule and for the contralateral lobe (extranodular tissue).
           
    123I was used and its biological half-life was converted into the effective half-life of 131I. Scintigraphy or US was used to measure the 131I volumes of nodule and lobe. The images were overexposed to reveal the lobe, a technique that made the lobe especially noticeable at 24 hours.
          
    Both in uptake and in dismission (biological half-life) the nodules varied considerably. 14 of the 26 patients had diminished levels, and in 3, the value was extremely short. Uptake of radioiodine was very low overall. The biological half-life was prolonged in the lobe when compared with the nodule, and the lobe’s uptake curve differed.
          
    The amount of radiation the lobe received was more than one tenth that received by the nodule. The dose received by extranodal tissue is higher than has been assumed, so it is reasonable to assume that posttreatment hypothyroidism may occur.
          

  • Yeung HWD, Humm JL, Larson SM (Mem Sloan-Kettering Cancer Ctr, New York)
    Radioiodine Uptake in Thyroid Remnants During Therapy After Tracer Dosimetry
    J Nucl Med 41: 1082-1085, 2000
          
    Before undergoing radioiodine therapy of residual tumor or thyroid remnant after thyroidectomy, patients usually have dosimetry with 131I to assess disease and to calculate uptake.
          
    From this study the therapeutic dose of 131I is evaluated. Whether the initial dosimetric dose affects the subsequent uptake of the therapeutic dose (stunning) has not been well studied. The sequential uptake of both the tracer and therapeutic dose of 131I was examined in a series of 12 consecutive patients.
         
    The patients were first subjected to thyroid dosimetry with 131I followed by a therapeutic 131I dose. The neck activity was calculated by the region-of-interest method in each case. Uptake after the therapeutic dose was expressed as a percentage of uptake after the diagnostic dose (% T/D).
          
    Of the 16 thyroid lesions in this series, 13 showed reduced uptake from the therapeutic dose, 2 remained the same, and 1 had increased uptake. The % T/D ranged from 7.0% to 388.5%. If the lesion with increased uptake was excluded from the data set, the range was 7.0% to 102.1% with an average of 50%.
         
    Linear regression between the percentage uptake of the diagnostic dose to the percentage uptake of the therapeutic dose results in a slope of 0.42, with a correlation coefficient of 0.75.
         
    The uptake of the therapeutic dose of 131I into thyroid lesions was significantly less than that predicted by the tracer dose of 131I in most patients. The stunning effect was present even for tracer doses of 131I as low as 37.0 MBq (1 mCi).
          

  • Cholewinski SP, Yoo KS, Klieger PS, et al (Univ of Rochester, NY)
    Absence of Thyroid Stunning After Diagnostic Whole-Body Scanning With 185 MBq 131I 
    J Nucl Med 41: 1198-1202, 2000
          
    This study evaluates the effect of a 185 MBq diagnostic dose of 131I when administered 72 hours before 131I ablation therapy. 122 patients treated by thyroidectomy for differentiated thyroid carcinoma were given 185 MBq diagnostic dose of 131I followed by a whole body diagnostic scan at 72 hours.
         
    Most patients were hospitalized and given 131I ablation therapy (5550 MBq) the same day as the diagnostic scan. A post-ablation whole body scan was obtained at 72 hours for comparison with the previous scan.
         
    No stunning effect was visually apparent when the ablation dose (131I) was dose on the day of the diagnostic scan completion. Therefore whole body scanning can yield high diagnostic accuracy and subsequent ablation success without concern for thyroid stunning.
          

  • Oyen WJG, Verhagen C, Saris E, et al (Univ Hosp Nijmegen, The Netherlands)
    Follow-Up Regimen of Differentiated Thyroid Carcinoma in Thyroidectomized Patients After Thyroid Hormone Withdrawal 
    J Nucl Med 41: 643-646, 2000
         
    This article attempts to optimize the diagnostic protocol for the follow-up of thyroidectomized patients after thyroid carcinoma.
         
    254 patients followed up for a mean 2.7 years were studied retrospectively. Patients underwent a low dose 131I diagnostic procedure under hyperthyroid conditions, thallium 201 (201Tl) scintigraphy and assessment of thyroglobulin under hypothyroid conditions. A total of 254 preablation and 586 follow-up studies were evaluated.
         
    Low-dose 131I screening before ablation was useful for estimating the size of thyroid remnants. Thyroglobulin concentrations <10 pmol/lL indicated absence of metastases. Undetectable thyroglobulin concentrations after ablation demonstrated the absence of tumor recurrence.
         
    Thyroglobulin levels >10 pmol/L indicated local recurrence or metastases, which required high dose 131I therapy. In such patients 201Tl imaging did not contribute to patient management.
         
    The role of 201Tl imaging in such patients is limited. It may be considered when low dose 131I screening is negative and thyroglobulin levels are increased or cannot be evaluated because of autoantibodies against thyroglobulin.
          

  • Ng DCE, Sundram FX, Sin AE (Singapore Gen Hosp) 
    99mTc-Sestamibi and 131I Whole-Body Scintigraphy and Initial Serum Thyroglobulin in the Management of Differentiated Thyroid Carcinoma 
    J Nucl Med 41: 631-635, 2000
            
    360 patients were studied prospectively. 99mTc-sestamibi whole-body scanning was done at least 5 weeks after thyroidectomy, followed by 131I whole-body scanning. No thyroxine suppression was given for 5 weeks. Radiologic and histopathologic examinations were done to determine the presence of metastases.
          
    The initial serum thyroglobulin levels were less than 30 ng/mL in 71.9% of the patients (group I), and 28.1% had levels of 30 ng/mL or more (group II). 82 of the 259 patients (group I) had positive 99mTc-sestamibi scans, and 113 had positive 131I scans.
          
    Of these patients with positive 131I scans, 71.7% also had positive 99mTc-sestambi scans. Of patients with positive 99mTc-sestamibi scans, 98.8% also had positive 131I scans. 81 of the 101 patients in Group II had positive 99mTc-sestamibi scans, and 97 had positive 131I scans. Of the patients with positive 131I scans, 83.5% also had a positive 99mTc-sestamibi scan. 
         
    All patients with positive 99mTc-sestamibi scans also had positive 131I scans. In group II, 27.2% had thyroid remnants and 68.8% had lymph node disease or metastases. 131I scanning demonstrated more thyroid remnants and lung metastases than did 99mTc-sestamibi scanning.
          
    131I scans are more sensitive than 99mTc-sestamibi scans in detecting thyroid remnants and lung metastases. However, 99mTc-sestamibi scanning appears to be more useful for demonstrating lymph node disease before initial 131I therapy.
            

  • Erdil TY, Ozker K, Kabasakal L, et al (Marmara Univ, Istanbul, Turkey; Med College of Wisconsin, Milwaukee; Istanbul Univ, Turkey; et al)
    Correlation of Technetium-99m MIBI and Thallium-201 Retention in Solitary Cold Thyroid Nodules With Postoperative Histopathology
    Eur J Nucl Med 27: 713-720, 2000
             
    The authors have compared thallium 201 (201TI) imaging with technetium 99m (99mTc) methoxyisobutylisonitrile (MIBI) imaging (early and delayed) in the differentiation of benign and malignant thyroid nodules.
           
    40 patients with cold thyroid nodules detected by 99mTc pertechnetate scanning and with dyskaryotic or atypical epithelial cells confirmed by fine-needle aspiration biopsy (FNAC) were studied. The patients underwent MIBI and 201TI scintigraphy 3 days apart. Subsequently all patients underwent thyroidectomy.
          
    A lesion-to-nonlesion ratio on early (ER) and delayed images (DR) was used in the semiquantitative analysis. Also, a retention index (RI) was determined by using the following formula: RI = (DR – ER) X 100/ER.
           
    21 patients had well differentiated thyroid cancer, and 19 had benign lesions. The ER did not differ significantly between malignant and benign lesions for 201TI or MIBI. However, malignant and benign lesions differed significantly in DR and RI with both modalities. The 2 groups did not show any statistical differences except in DR and RI in malignant nodules.
          
    Based on these threshold levels, ER MIBI had a sensitivity of 90.5%, a specificity of 36.8%, and an accuracy of 65%. For DR MIBI, these values were 61.9%, 94.7%, and 77.5% respectively. The RI MIBI had a 95.2% sensitivity, 89.4% specificity, and a 92.5% accuracy. For ER 201TI, these values were 85.7%, 47.3%, and 67.5%, respectively. The DR 201TI had an 80.9% sensitivity, 73.6% specificity, and 77.5% accuracy. For RI 201TI, these corresponding values were 90.5%, 94.7%, and 92.5%.
           
    The DR for MIBI and 201TI is better than the ER for detecting malignant nodules. The RI for both MIBI and 201TI is of more value than the DR for differentiating malignant from benign thyroid nodules.
             

  • Fatourechi V, Hay ID, Mullan BP, et al (Mayo Clinic, Rochester, Minn)
    Are Posttherapy Radioiodine Scans Informative and Do They Influence Subsequent Therapy of Patients With Differentiated Thyroid Cancer?
    Thyroid 10: 573-577, 2000
          
    This study evaluates the efficacy of a posttherapy scans (PTSs) to visualize metastases that may not be apparent on a lower dose diagnostic scan.
          
    81 patients were studied (64 had papillary thyroid cancer, and 17 had follicular thyroid cancer). All patients underwent both a diagnostic whole-body scan and a PTS. A total of 117 PTSs were examined.
          
    At the time of PTS, 68 patients had clinical or radiologic evidence of metastatatic or residual disease. Known disease was located in neck on 63 scans, mediastinum on 23, lung on 35, bone on 14, trachea on 16, esophagus on 5, and brain on 2 scans. Focal areas of abnormal uptake not visualized in diagnostic scans could be seen on 15 PTSs (13%).
          
    Areas with abnormal new uptake included the neck on 5 scans, lung on 5, mediastinum on 4, bone on 2, and adrenal gland on 1 scan. In 9% of patients, PTS findings affected plans for subsequent diagnostic scanning and 131I therapy or altered the patients’ risk group category.
           

  • Alnafisi NS, Driedger AA, Coates G, et al (Univ of Western Ontario, London; McMaster Univ, Hamilton, Ont)
    FDG PET of Recurrent or Metastatic 131I-Negative Papillary Thyroid Carcinoma
    J Nucl Med 41: 1010-1015, 2000
          
    The authors have evaluated the value of FDG PET in the diagnosis of papillary thyroid cancer with negative 131I total body scan and increased thyroglobulin levels after total thyroidectomy.
         
    11 asymptomatic thyroidectomised patients (for papillary cancer) with negative 131I total body scan but raised thyroglobulin levels (no thyroxine therapy) were studied. All of them had also been treated by 131I ablation and all known metastases treated. Imaging failed to demonstrate residual tumor before PET. 
         
    After PET, all underwent CT scan, sonography and biopsy of neck lesions. All patients had FDG uptake in the neck or upper mediastinum (initial scans of 10 and in repeat scan of 1). Sonographically guided biopsy confirmed malignancy in 6 patients, were normal in 1, and was nondiagnostic in 2. 2 did not undergo biopsy. 
         
    Imaging with FDG resulted in treatment modifications in 7, resulting in surgery and external beam radiotherapy in 3, surgery in 1 and external beam radiotherapy in 2. In all those subjected to surgery, histopathology was positive.
         
    FDG PET scan enabled detection of disease in 7 patients out of 11. In conjunction with sonography and biopsy it resulted in the treatment changes in most patients.
          

  • Brandt-Mainz K, Muller SP, Gorges R, et al (Universitatsklinikum Essen, Germany)
    The Value of Fluorine-18 Fluorodeoxyglucose PET in Patients With Medullary Thyroid Cancer
    Eur J Nucl Med 27: 490-496, 2000
          
    The value of fluorine 18 (18F) FDG PET in following up patients with medullary thyroid cancer (MTC) has been investigated. 
         
    20 patients with increased calcitonin levels or sonographic abnormalities in the neck underwent 18F-FDG PET; findings were validated by histologic evaluation, CT findings, or selective venous catheterization results.
          
    13 of 17 had a tumor detected on 18F-FDG PET and validated by histology or CT. 5 Patients had completely negative scans (PET), including 4 false negative scans. One patient with 18F-FDG accumulation in pulmonary lesions from silicosis and 1 patient with a neck lesion not subjected to histologic evaluation were excluded from the analysis.
          
    In all 18F-FDG PET detected 12 of 14 metastases in the neck, 6 of 7 in the mediastinum, 2 of 2 in the lungs, and 2 of 2 in bone. None of the diagnostic modalities could localize tumor in 2 patients with increased calcitonin levels. The sensitivity of the 18F-FDG PET was 76%.
               

  • Angusti T, Codegone A, Pellerito R, et al (Ospedale Mauriziano Umberto I Torino, Italy)
    Thyroid Cancer Prevalence After Radioiodine Treatment of Hyperthyroidism
    J Nucl Med 41: 1006-1009, 2000
          
    Radioiodine therapy may be a risk factor for the misdiagnosis of cancer. This possibility has been investigated.
          
    Data from 6647 patients undergoing 131I therapy for hyperthyroidism was studied. 76% had an autonomously functioning node or a toxic multinodular goiter and 24% had Graves disease.
          
    After 131I therapy, only 0.15% showed evidence of cancer. None of those with Graves disease had cancer. 5 of the 10 patients with cancer had earlier been treated. This incidence was not different from that in the general population.        
                                                                                  

  • Gupta NC, Graeber GM, Bishop HA, (West Virginia Univ, Morgantown)
    Comparative Efficacy of Positron Emission Tomography With Fluorodeoxyglucose in Evaluation of Small (<1cm), Intermediate (1 to 3 cm), and Large (>3cm) Lymph Node Lesions            
    Chest 117: 773-778, 2000            
                                             
    The capability of FDG PET to aid in the detection of metastatic disease in lymph nodes of various sizes has been compared with that of CT.                                      
                                                                   
    118 patients with known or suspected non-small-cell lung cancer underwent CT and FDG PET studies. The results were compared with histological results from sampled lymph nodes of 54 patients.                  
                                                                 
    Of 118 patients, 79 had malignant primary lesions and 39 had benign lesions. Histologically there were 49 adenocarcinomas and 13 squamous cell carcinomas, 16 non-small-cell, 3 small cell, and 6 other carcinomas.               
                                                                           
    Of 168 lymph nodes sampled 53 were <1cm, 107 were 1-3 cm and 8 were >3cm in size. There were 53 malignant nodes.  
                                                                     
    Most lesions of <1cm were localized in the hilar/mediastinal nodes. The overall sensitivity, specificity, and accuracy of FDG PET and CT for staging mediastinal nodes were 96% and 80%, 93% and 95%, 94% and 92% respectively.           
                                                     
    The sensitivity, specificity, and accuracy for detecting lymph nodes <1cm, 1-3cm, and >3cm were 80%, 100%, and 100%; 95%, 91%, and 75%; and 92%, 95%, and 88% respectively.                             
                                              
    FDG PET results changed N staging in 25 patients and aided in the detection of disease in 15 of 17 lymph nodes missed by CT. 
                                                        
    FDG PET is more effective than CT for detecting metastatic disease in mediastinal lymph nodes.                    
                        

  • Yamamoto Y, Nishiyama Y, Satoh K, et al (Kagawa Med Univ, Japan)                      
    Comparative Evaluation of Tc-99m MIBI and TI-201 Chloride SPECT in Non-Small-Cell Lung Cancer Mediastinal Lymph Node Metastases                   
    Clin Nucl Med 25: 29-32, 2000                           
                                      
    Two nuclear medicine studies have been compared for use in assessing the mediastinal lymph nodes in non-small cell lung cancer: hexakis 2-methoxy isobutyl isonitrile (technetium 99m [99mTc] MIBI) and thallium 201 (201TI) chloride SPECT.   
                                     
    The study included 41 patients with non-small cell lung cancer (24 adenocarcinomas, 14 squamous cell carcinomas, 2 with adenosquamous cell carcinoma, and 1 with large cell carcinoma).               
                                    
    Simultaneous dual-isotope SPECT scanning with 201TI and 99mTc-MIBI was done to evaluate mediastinal lymph node involvement, which was later confirmed by histopathology.               
                               
    32% had pathologically confirmed node involvement.                            
                                 
    Both early and delayed 99mTc-MIBI SPECT scan had a sensitivity of 69% and a specificity of 96% for detection of nodal metastasis.                              
                                              
    In comparison both early and delayed 201TI-chloride SPECT had a sensitivity of 92% with a specificity of 93% and 96% respectively.                                              
                                                   
    201TI SPECT scan is superior to 99mTc-MIBI SPECT for detection of mediastinal lymph node involvement.        
                   

  • Whiteford MH, Whiteford HM, Yee LF, et al (Washington Univ, St Louis)                                                            
    Usefulness of FDG-PET Scan in the Assessment of Suspected Metastatic or Recurrent Adenocarcinoma of the Colon and Rectum                                                                           
    Dis Colon Rectum 53: 759-770, 2000                                                                                 
                                                                                                                    
    The records of 105 patients who had had 101 CT and 109 FDG PET scans for suspected metastatic or recurrent colorectal adenocarcinoma were reviewed. The findings were confirmed at surgery by histopathology and by the clinical course.        
                                                                                                                               
    The overall sensitivity and specificity of FDG PET were 87% and 68% respectively in detecting clinically relevant tumor. For CT plus other conventional diagnostic studies these values were 66% and 59% respectively.                             
                                                                                                  
    The sensitivity of FDG PET was 58% for detecting mucinous cancer and 92% for non mucinous cancer.                          
                                                                                     
    For detecting locoregional recurrence the sensitivity of FDG PET and CT plus other conventional studies was 94% and 67% respectively.                                                                                        
                                                                                                         
    Compared with CT plus other conventional studies, FDG PET beneficially altered clinical management in 26% of cases.         
                                                                                 

  • Acland KM, O’Doherty MJ, Russell-Jones R (Guy’s and St Thomas’ Hosp, London)                               
    The Value of Positron Emission Tomography Scanning in the Detection of Subclinical Metastatic          Melanoma                            
    J Am Acad Dermatol 42: 606-611, 2000                 
                                                              

    Whole-body FDG-PET scans were performed after a 6-hour fast. The study group included those patients with primary cutaneous malignant melanoma in whom PET scanning revealed in-transit or regional spread to lymph nodes; as well as those patients known to have regional spread and in whom PET scans revealed distant metastases.                 
                                                                                                 
    False negative results were those with negative scans with positive histology. False positive results were those with suspect scan and negative histology or no subsequent progression of disease.                                               
                                                                                     
    The overall sensitivity of PET scanning was 78% with a specificity of 87%. On subset analyses with the M. D. Anderson staging system the sensitivity was 50% for stage I disease and 33% for stage II disease with specificities of 87% and 100% respectively. For stage II disease the sensitivity of PET scanning was 93% with a specificity of 50%. Restaging of the disease occurred in 35% of patients with true positive scans.                                                                  
                                                                                                  

  • Eigtved A, Andersson AP, DahlstrØm K, et al (Copenhagen Univ)                     
    Use of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in the Detection of Silent      Metastases from Malignant Melanoma                           
    Eur J Nucl Med 27: 70-75, 2000                                          
                                                                                
    The staging of malignant melanoma has been compared between fluorine 18 (18F) FDG and by conventional methods.     
                                                                           
    38 patients (stage II/III) with malignant melanoma underwent PET imaging with 18F-FDG and the results were compared with those of clinical examination and other imaging methods (CT, US, radiography, and liver function tests). Histologic data and findings of clinical follow-up were noted.                                                    
                                                              
    A histologic diagnosis was possible in 29 of 38 patients (25 were malignant and 4 were benign). In the remaining 9 cases the patients refused biopsy or the location of the mass was unapproachable. The mean follow-up was 48 months (44-56 months).
                                                                                    
    With 18F-FDG PET, the sensitivity and specificity of foci overall were 97% and 56%, respectively compared with 62% and 22% respectively by routine methods. For intraabdominal foci sensitivity and specificity were 100% and 100% respectively, for both 18F-FDG PET and routine methods.                                     
                                                                                
    The figures for pulmonary and intrathoracic foci were 100% and 33% respectively. Of patients evaluated 34% would not have their melanoma staged correctly by conventional methods alone.                                                 
                                                                                                    
    The discovery of disseminated disease can spare the patient from extensive mutilating surgery. 18F-FDG PET should only be used along with a thorough clinical examination.                                                                     
                                                                               

  • Tyler DS, Onaitis M, Kherani A, et al (Duke Univ, Durham, NC)                                
    Positron Emission Tomography Scanning in Malignant Melanoma: Clinical Utility in Patients With Stage III Disease                         
    Cancer 89: 1019-1025, 2000                        
                                              
    This is a prospective evaluation of PET in malignant melanoma.                       
                                                        
    The patients studied had clinically evident stage III disease in the form of palpable lymph node disease, in-transit disease, or both. In such cases, the sensitivity and specificity of PET could be measured and the limits of resolution better defined.    
                                           
    It would also be possible to determine how often PET identified unsuspected metastatic disease and how often these findings affected clinical management.                            
                                                  
    All 95 patients studied were considered for further surgery. Two independent observers assessed FDG PET activity independently and without knowledge of clinical or pathologic results. Of the 234 areas pathologically evaluated, 165 were confirmed to be malignant melanoma.                                     
                                                              
    The sensitivity of PET scanning, which identified 144 areas as positive was 87.3%. Included in the 21 missed areas of melanoma were 10 microscopic foci, 9 foci <1cm, and 2 foci >1cm.                                 
                                                          
    PET scan had a specificity of 43.5%, a negative predictive value of 58.8%, and a positive predictive value of 78.6%.          
                                                           
    13 of the 39 false positive areas could be attributed to recent surgery. Addition of clinical information improved the predictive value of a positive scan to 90.6%. 36 areas of increased PET activity represented unsuspected metastatic disease and the clinical management was changed in 15 of 95 patients.                      
                                                      
    PET scan is sensitive in the detection of metastatic disease in malignant melanoma, particularly unsuspected disease in stage III malignant melanoma. The abnormalities so detected can be further evaluated by a localized CT scan.    
              

  • Crippa F, Leutner M, et al (Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy)
    Which Kinds of Lymph Node Metastases Can FDG PET Detect? A Clinical Study in Melanoma
    J Nucl Med 41: 1491-1494, 2000
        
    The diagnostic accuracy of FDG PET for lymph node metastases has been evaluated and the smallest detectable volume of disease determined. 
                          
    56 lymph node basins in 38 patients were studied preoperatively with FDG PET. Patients studied had a clinical or instrumental diagnosis of lymph node metastases from melanoma. Subsequently all these areas were subjected to surgery. The results of FDG PET were compared with the post operative histopathology results. 
               
    The efficacy of FDG PET was good for the diagnosis of involved lymph node basins. It had a specificity of 84%, sensitivity of 95%, accuracy of 91%, a positive predictive value of 92% and a negative predictive value of 89%. 
         
    Histological evidence of metastases was seen in 114 of 647 surgically removed lymph nodes. FDG PET had a high sensitivity of >93% only for metastases with capsular infiltration or with greater than 50% involvement. Detection rate of FDG PET for metastases greater than 10 mm was 95%, the rate for metastases of 6-10 mm size was 83% and for metastases 5 mm or less in size the detection rate was 23%.  
                
    FDG PET has good sensitivity but false positive results are possible. 
                                        

  • Shah N, Hoskin P, et al (Mount Vernon Hosp, Northwood, England)     
    The Impact of FDG Positron Emission Tomography Imaging on the Management of Lymphomas    
    Br J Radiol 73: 482-487, 2000       
                         
    The role of FDG PET in the management of lymphomas has been assessed.      
                    
    29 patients undergoing FDG PET imaging during treatment of lymphoma have been reviewed retrospectively (12 Hodgkin’s and 17 non-Hodgkin’s lymphoma (NHL)).      
                                
    FDG PET imaging contributed additional information to clinical and CT findings in 41% of the patients with both positive and negative scans. There were 2 false positive FDG PET scans, reflecting FDG uptake in extranodal sites. The findings of FDG PET affected clinical management in 34% of the patients. In 2 patients the initial management was changed and in 8 consolidation therapy after completion of initial chemotherapy was altered.                 
                               
    Management changes were made for 6 patients with high grade NHL, 2 with low grade NHL and 2 with Hodgkin’s disease. 
                    
    This noninvasive modality enables evaluation of potential sites of active disease and compliments CT in the assessment of lymphoma.               
                                                                                             

  • Delcambre C, Reman O, et al (Centre Francois Baclesse, Caen, France; Centre Hospitalier Regionale Universitaire, Caen, France)                      
    Clinical Relevance of Gallium-67 Scintigraphy in Lymphoma Before and After Therapy    
    Eur J Nucl Med 27: 176-184, 2000     
                          
    The staging of lymphoma with 67Ga scintigraphy has been compared with staging with clinical assessment and conventional imaging (CI).           
                                                 
    62 patients were submitted to 67Ga scintigraphy (86 scans). 52 patients had Hodgkin’s lymphoma (HL) and 10 had non-Hodgkin’s lymphoma (NHL). In 44 patients it was done at diagnosis and in 42 patients after treatment. Examination was done with 185 to 220 MBq 67Ga citrate and planar and SPECT studies. Assessment with CI consisted of plain X-ray chest, CT scan chest, abdomen and pelvis, abdominal US, lymphography, bone marrow biopsy, and when necessary MRI and bone scintigraphy.      
                                                
    For individual sites, before treatment there was complete agreement between the two methods in 57% of cases. More sites were demonstrated by clinical examination and CI than by scintigraphy in 27% and 67Ga imaging showed more sites than CI in 11%.
                                  
    Clinical disease stage at scintigraphy only was in accordance with that which used all diagnostic procedures in 77% of cases. After treatment, CI and scintigraphic studies were normal in 11 patients all but one of whom remained in complete remission on a 31-month follow-up. 31 patients had a residual mass radiologically. Scintigraphy was normal in 71% of these patients.   
                              
    Scintigraphy demonstrated abnormal uptake in 9 of 31 patients with a large residual mass, 8 of whom had active disease and one with complete remission at 30-month follow-up.      
                                            
    67Ga imaging cannot replace CI in the diagnosis of lymphoma, but it may depict additional disease sites in more than 10% of cases, thus permitting clinical upstaging and better prognostication. After treatment it enables one to avoid unnecessary complementary therapy.       
                                                                     

  • Frohlich DEC, Chen JL, et al (Harvard Med School, Boston)
    When Is Hilar Uptake of 67Ga-Citrate Indicative of Residual Disease After CHOP Chemotherapy
    J Nucl Med 41: 269-274, 2000
                                   
    The patterns of Gallium hilar uptake (HU) after chemotherapy (CHOP) to treat NHL were analyzed including findings associated with hilar lymphoma (HL) versus benign HU.  
                          
    This prospective study included review of 930 67Ga-citrate scans, 698 planar and 232 thoracic SPECT from 100 patients with NHL (29 with low-grade disease, 60 with intermediate disease and 11 with high-grade disease). All patients had received CHOP therapy and were followed up for a mean of 36 months. The median number of planar gallium scans obtained during follow-up was 7.  
                                      
    The prevalence and patterns of HU were analyzed, including the relationship between HU and chemotherapy dose. Benign and malignant HU were differentiated based on clinical outcomes and changes over time on correlative CT scans or radiographs. 
                                        
    79% of patients had HU after CHOP including 33% with HU on SPECT scans alone. The median duration of persistent HU was 27% after onset. At baseline 52% had HU and 60% had HL. During CHOP therapy, 59% had HU but only 2% had HL. After CHOP therapy the figures were HU 52% and HL 6% respectively and HU 76% and HL 9% at follow-up.   
                                                       
    The presence of benign HU was not significantly related to chemotherapy dosage. In about 90% of patients, HU was symmetric and less intense then at baseline (correlated with benign HU). In contrast asymmetric HU of equal intensity to the original disease was strongly correlated with the presence of HL.    
                                   

  • Lapela M, Eigtved A, et al (Univ of Turku, Finland; Copenhagen Univ)
    Experience in Qualitative and Quantitative FDG PET in Follow-up of Patients With Suspected Recurrence From Head and Neck Cancer        
    Eur J Cancer 36: 858-867, 2000  
                    
    The value of FDG PET (a noninvasive method) in detecting recurrent head and neck cancer is investigated. 
                   
    62 FDG PET studies were obtained in 56 patients (a total of 81 lesions). All were clinically suspected of having recurrent head and neck carcinoma. The PET images were visually interpreted. Tracer uptake was quantitated as the standardized uptake value adjusted for body weight.   
                                
    Visual interpretation of the PET images for the presence of malignancy had a sensitivity between 84% to 95% and a specificity of 84% to 93% depending on the selected scheme for lesion grading.   
                                  
    Malignant lesions accumulated much more FDG than benign lesions. However FDG uptake values between these two groups overlapped greatly. Thus the most accurate quantitative analysis in recurrence detection was inferior to visual interpretation, these accuracies being 75% and 89%, respectively.             
                          

  • Stokkel MPM, Moons KGM, et al (Univ Hosp Utrecht, The Netherlands)
    18F-Fluorodeoxyglucose Dual-Head Positron Emission Tomography as a Procedure for Detecting Simultaneous Primary Tumors in Cases of Head and Neck Cancer
    Cancer 86: 2370-2377, 1999
                       
    This study compares the ability of 18F-fluorodeoxyglucose dual-head PET (FDG PET) with standard clinical tests in detecting secondary primary tumors. 
                                   
    This prospective study includes 68 patients with a primary tumor of the oral cavity or oropharynx. Each patient had a thorough clinical examination (excluding panendoscopy) before FDG PET was performed.    
                             
    Addiction to alcohol or smoking was documented and the patients were divided into groups on the basis of these habits. The follow-up period was at least 6 months with a view to identify synchronous tumors missed by FDG PET.    
                                 
    FDG PET detected secondary primary malignant tumors in 12 patients (18%). Only 5 of these tumors were detected by clinical or radiologic examination (7%). All but one of the tumors detected by FDG PET were located in the epithelium of the upper digestive tract/respiratory tract. None of these patients had simultaneous or synchronous primary tumors during the follow-up period.             
                                                              
    FDG PET is an attractive option in the assessment of patients with head and neck cancer.          
       

  • Boerner AR, Weckesser M, et al (Univ Hosp Dusseldorf, Germany; Research Centre Julich, Germany, et al)
    Optimal Scan Time for Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Breast Cancer 
    Eur J Nucl Med 26: 226-230, 1999
           
    A 3-hour imaging protocol was performed in women with primary breast cancer to determine whether this approach would improve tumor detectability and image contrast. 
          
    29 women with tumors of 2 cm or greater in diameter found to be malignant by biopsy were studied. 370 to 740 Mbq fluorine 18-FDG and scanned in the prone position. Data were obtained at 0 to 40 minutes, 1.5 hours and 3 hours after injection. 
          
    Tumor to nontumor and tumor to organ ratios were significantly greater for the images obtained at 3 hours than for those obtained at 1.5 hours. Lesion detectabilities at 1.5 and 3 hours were 83% and 93% respectively.
            
    Obtaining the scan at 3 hours appears to increase the diagnostic sensitivity of FDG PET.   
                                                                

  • Yutani K, Shiba E, et al (Kaizuka City Hosp, Japan; Osaka Univ, Japan)  
    Comparison of FDG-PET with MIBI-SPECT in the Detection of Breast Cancer and Axillary Lymph Node Metastasis      
    J Comput Assist Tomogr 24: 274-280, 2000            
                                        
    This is a comparative study of two non invasive techniques, FDG-PET and 99mTc-methoxyisobutylisonitrile (MIBI-SPECT) in the detection of breast cancer and axillary lymph node metastases in the same patients.  
                                                    
    40 women (25-86 years) with suspected breast cancer and in whom biopsies or mastectomies were performed underwent both FDG-PET and MIBI-SPECT within 3 days. The images were assessed visually and calculation of count ratio between tumor and normal (T/N ratio) tissue was performed.               
                                                             
    38 cancers and 2 benign breast lesions were detected. For breast cancer the sensitivity of FDG-PET was 78.9% and that of MIBI-SPECT was 76.3%. For axillary lymph node metastases the sensitivity of FDG-PET was 50% and that of MIBI-SPECT was 37.5%. FDG-PET demonstrated a significantly higher T/N ratio of breast cancer that was seen with MIBI-SPECT. Tumor uptake was obscured occasionally by non-malignant diffuse uptake of FDG in the breast and accumulation of MIBI in the heart and liver.           
                                                                                        
    Both FDG-PET and MIBI-SPECT have comparable capabilities in the detection of breast carcinoma. However, neither modality has enough sensitivity to rule out axillary lymph node metastases.             
                                                                            

  • Obwegeser R, Berghammer P, et al (Univ of Vienna)            
    A Head-to-Head Comparison Between Technetium-99m-Tetrofosmin and Technetium-99m-MIBI    Scintigraphy to Evaluate Suspicious Breast Lesions           
    Eur J Nucl Med 26: 1553-1559, 1999                
                                                                                                         
    The diagnostic value of 99m (99m Tc)-tetrofosmin and 99mTc-MIBI have been compared to evaluate suspicious breast cancer.
                                                
    The 2 radiopharmaceutical agents were administered randomly on different days in 101 women (103 breast tumors) in a prospective open diagnostic trial. Planar images and SPECT scans were obtained and tumors were subjected to histopathology.
                                                          
    The sensitivity of 99mTc-tetrofosmin and 99mTc-MIBI was only 44% and 46% respectively for planar images. For SPECT sensitivity was improved to 70% and 69% respectively. Specificity for planar images was 83% and 87% and for SPECT 70% and 78% respectively. The positive predictive value was 76% and 81% respectively for planar images and values were comparable for SPECT. The negative-predictive values were 54% and 57% for planar images and 65% and 67% respectively for SPECT. 
                                                                   
    The 2 agents have similar diagnostic value. SPECT improves sensitivity but not specificity. It however provides additional information about tumor location.               
                                                                                                                                                                                     

  • Rostom AY, Powe J, et al (King Khalid Univ, Saudi Arabia)
    Positron Emission Tomography in Breast Cancer: A Clinicopathological Correlation of Results
    Br J Radiol 72: 1064-1068, 1999          
                          
    The diagnostic value of PET in patients with primary, recurrent or metastatic breast disease (cancer) was evaluated. 
                                     
    109 selected breast cancer patients who underwent FDG-PET (whole body) were included in this study. In addition all patients underwent bone scans, liver ultrasonography (US) or abdominal CT plus chest CT or radiography and 86 patients underwent mammography. Histological data was available in 105 patients. 
                       
    The sensitivity, specificity and accuracy of PET imaging of the primary tumor and lymph nodes were evaluated. For patients with metastases, the accuracy of PET, was compared with that of other imaging modalities. 
                         
    For tumor evaluation PET had an accuracy of 89% with a false positive rate of 3% and false negative rate of 8%. Accuracy was 91% for lymph node evaluation with a false negative rate of 10%.
                       
    PET had an accuracy of 90% versus 72% for mammography (86 patients) for primary tumor. PET findings in 19 patients with metastases agreed with those of other imaging studies.                       
                                                                                                           
    PET can be used for diagnosis staging and evaluation of therapy response in cases of breast cancer.           
                                                                                           

  • Ortapamuk H, Ozmen MM, et al (Ankara Numune Hosp, Turkey)
    Role of Technetium Tetrofosmin Scintimammography in the Diagnosis of Malignant Breast Masses and Axillary Lymph Node Involvement: A Comparative Study With Mammography and Histopathology
    Eur J Surg 165: 1147-1153, 1999
                                                     
    The role of technetium 99m (99mTc) tetrofosmin scintimammography has been examined in the detection of breast cancer and axillary lymph node metastases. 
                                        
    128 women with breast masses underwent clinical examination and standard mammogram. Scintigram (mammography) was performed within 1 week of mammography for women with palpable masses or mammographic evidence of abnormalities or both. The final diagnosis was determined by excision biopsy. 
                                                 
    The contol group (30 women) with no palpable mass who had been referred for myocardial perfusion scintigraphy. The sensitivity, specificity and positive and negative predictive values of scintimammography were compared with those of mammography.
                                
    Of 80 scintimammography positive lesions, 78 were malignant and 2 benign. Of 48 scintimammography negative lesions, 44 were benign and 4 were malignant. 
                                                     
    For 99mTc scintimammography, the sensitivity, specificity and positive and negative predictive values were 95%, 96%, 97% and 92% respectively. For standard mammography, these values were 87%, 26%, 68% and 52% respectively. 34 false positive mammograms were changed into true negative findings with scintimammography, at the expense of 4 false negative results. The sensitivity and specificity of scintimammography for axillary lymph node metastases were 72% and 100% respectively.

    99mTc-tetrofosmin scintigraphy is helpful in the detection of breast cancer and axillary nodal metastases. It may help prevent unnecessary surgery in doubtful cases.                         
                                                                                

  • Jansen L, Doting MHE, et al (The Netherlands Cancer Inst, Amsterdam; Groningen Univ, The Netherlands)
    Clinical Relevance of Sentinel Lymph Nodes Outside the Axilla in Patients with Breast Cancer
    Br J Surg 87: 920-925, 2000
                                  
    Patients with early stage breast cancer were examined to characterize the incidence of sentinel lymph nodes (SLNs) outside of the axilla, their identification and the clinical relevance. 
                                        
    113 women (mean age 58 years) with T1-3, N0, M0 breast cancer were studied. SLNs were identified by blue staining and gamma probe. All SLNs were examined histopathologically and by immunohistochemistry. Of special interest were SLNs outside the area of a level I-II axillary dissection. Regardless of SLN status all patients underwent level I-III axillary dissection.
                        
    SLNs outside the axilla were common (21 patients i.e. 19%). Most of these patients (18 or 86%) had SLNs both in the axilla and at another site. However in 3 patients (14%) the only SLN identified were outside the axilla. Of the 30 SLNs outside the axilla, 22 (73%) were harvested (more difficult than SLNs in the axilla). 
                               
    Of the 21 patients with SLNs outside the axilla, 8 had regional metastases. 4 of them had no metastases outside the axilla and 1 had metastases in SLNs in the interpectoral fossa and at level I of the axilla. 
                                 
    Therefore, biopsy of the SLNs outside the axilla did not change staging and postoperative treatment in these 5 patients. In the remaining 3 patients tumor positive SLNs were found in the internal mammary chain and these patients were upstaged to pT1N3 (2 patients) and pT3N3 (1 patient).                          
                     
    These latter 3 patients received radiotherapy to the internal mammary chain based on SLNs outside the axilla. None of the patients experienced complications as a result of SLN harvesting. 
                              
    SLN harvesting was technically difficult, but did not increase the morbidity. Biopsy of SLNs outside the axilla changed staging and treatment in only 3 patients (2.5%).                      
                                               

  • Kabasakal L, Halac M, et al (Cerrahpasa Med Faculty, Istanbul, Turkey)
    The Effect of P-Glycoprotein Function Inhibition With Cyclosporine A on the Biodistribution of Tc-99m Sestamibi           
    Clin Nucl Med 25: 20-23, 2000            
                                                     
    Verapamil and cyclosporine are 2 drugs that can partially or completely reverse drug resistance and restore sensitivity of cytotoxic agents by inhibiting P-glycoprotein transport function. The effect of cyclosporine on the biologic distribution of 99mTc sestamibi was examined in vivo in 5 patients with alopecia and 2 patients who underwent renal transplantation and were treated with cyclosporine.              
                                                  
    All 7 patients were evaluated before and at 2 weeks after receiving cyclosporine. Patients underwent 99mTc sestamibi scintigraphy. Planar abdominal images were taken at 5, 30, 60, 120 and 180 minutes after injection and after determination of liver-heart ratios. All patients underwent evaluation of plasma cyclosporine, bilirubin levels, liver enzymes and creatinine levels.
                                                  
    The plasma cyclosporine levels were increased to 400 pg/dL in 3 patients, and the liver-heart ratio rose significantly after cyclosporine administration. There was a delay in 99mTc sestamibi excretion and liver uptake rose after cyclosporine administration. Differences were 17% and 38%, respectively, at 5 and 180 minutes.
                                                  
    The highest liver retention was observed in patients with cyclosporine toxicity. Inhibition of P-glycoprotein transport delyas liver excretion and enhances liver uptake of 99mTc sestamibi.      
                                                                                           

  • Watanabe H, Shinozaki T, et al (Gunma Univ, Japan; Toho Hosp, Gunma, Japan)
    Glucose Metabolic Analysis of Musculoskeletal Tumours Using 18Fluorine-FDG PET as an Aid to Preoperative Planning                 
    J Bone Joint Surg Br 82-B: 760-767, 2000                   
                                                                   
    Tumor tissue generally displays enhanced glycolysis and hence 18-FDG has been used as an imaging agent in conjunction with PET not only to evaluate primary brain tumors but also to distinguish between other lesions such as pancreatic carcinoma and mass forming pancreatitis.                        
                                                                                                 
    The standardized uptake value (SUV) can be used as a prognostic factor for pancreatic carcinoma when calculated with FDG-PET. Scanning with FDG was performed on patients with tumors involving the musculoskeletal system to evaluate the role of FDG-PET in operative planning.                     
                                                                                 
    FDG-PET scanning was performed in 55 patients (26 M, 29 F, mean age of 45.3 years). All the patients were suspected to have bone or soft tissue tumors. After calculation of the SUV of FDG, the patients were divided into high SUV (>1.9) and low (<1.9) groups to distinguish malignant from benign lesions.                    
                                                      
    The sensitivity of PET was 100% for diagnosis of malignancy with a specificity of 76.9% and an overall accuracy of 83%. The mean SUV for metastatic lesions was twice the mean SUV for primary sarcomas.         
                                                                     
    SUV has a role in the differentiation of malignant from benign lesions. However some benign lesions such as schwannomas had high SUVs and thus histopathology of the lesion is important.                      
                                                                 
    Reverse transcription polymerase chain reaction analysis demonstrated that the RNA message of phosphohexose isomerase (PHI/autocrine motility factor, a critical enzyme in glucose metabolism was augmented in high FDG-uptake lesions, but not low FDG uptake lesions.                         
                                                                                                          
    This suggests that there may be an association between the high expression of the PHI message and accumulation of FDG in musculoskeletal tumors.                   
                                                                                                                                                                                            

  • Schwarzbach MHM, Willeke F, et al (Univ of Heidelberg, Germany; German Cancer Research Ctr, Heidelberg, Germany)
    Clinical Value of [18-F] Fluorodeoxyglucose Positron Emission Tomography Imaging in Soft Tissue Sarcomas                  
    Ann Surg 231: 380-386, 2000       
                                                             
    The use of FDG-PET for evaluation of suspected soft tissue sarcomas, including noninvasive tumor grading, identification of viable tumor tissue, and posttreatment follow-up, has been studied.    
                                                                  
    The analysis includes prospectively collected data on 59 suspected primary or recurrent soft tissue sarcomas in 50 patients. The uptake of FDG was evaluated qualitatively and quantitatively with standardized uptake values (SUVs) calculated in tumor and in normal muscle tissue. The FDG-PET findings were correlated with surgical and follow-up data.       
                                            
    FDG-PET had a sensitivity of 91% and specificity of 88% in the detection of primary soft tissue sarcomas. For local recurrences, sensitivity was 88% and specificity 92%. All intermediate and high-grade sarcomas (primary and locally recurrent) were accurately visualized and differentiated from control muscle tissue.     
                                                 
    However, in half of the low-grade sarcomas, FDG uptake was equal to that of normal muscle. No FDG accumulation was seen in benign soft tissue tumors, but it did accumulate in inflammation. Although FDG SUVs were significantly correlated in with sarcoma grade, they did not reflect the tumor size or histology.   
                                                                                                    
    FDG-PET has promise as a complementary preoperative imaging study for soft tissue sarcomas.
       

  • Durand E, Prigent A (Hopitaux de Paris)
    Can Dimercaptosuccinic Acid Renal Scintigraphy Be Used to Assess Global Renal Function?
    Eur J Nucl Med 27: 727-730, 2000
      
    The goal of this study is to determine whether renal absolute DMSA uptake can reflect the absolute renal function.
    A simple monoexponential model was used to complete the absolute DMSA uptake in the event of injury to one kidney.
    The results of this experiment indicate that the assumption that absolute DMSA uptake accurately reflects absolute renal function may lead to more than a 50% overestimation of the function of both the normal and impaired kidney.
    It was also found that the error becomes increasingly important the later the measurement is made and the more impaired the kidney is at the time.
    DMSA can provide reliable quantification of relative renal function, but it should not be used in the assessment of absolute renal function because significant overestimation is possible.
        

  • Pusuwan P, Reyes L, et al (Great Ormond Street Hospital for Children, NHS Trust, London)
    Normal Appearances of Technetium 99 Dimercaptosuccinic Acid in Children on Planar Imaging
    Eur J Nucl Med 26: 483-488, 1999
      
    The appearances of 99mTc DMSA images of children with normal kidneys on renal arteriography were analyzed.
      
    32 children undergoing renal arteriography with normal results also underwent DMSA imaging. The criteria for high quality 99mTc DMSA imaging were based on kidney outline and contrast between the inner and outer part of the kidney. Most images were of high quality. The most common feature was a round or flat contour present in 50% and 24.8% respectively. The were a small number of unusual appearances. The mean differential function of the left kidney was 51% (45%-57%).
       

  • Peng N-J, Kwok CG, et al (Veterans gen Hosp, Kaohsiung, Republic of China; Veterans Gen Hosp, Taipei, Republic of China; et al)
    Posterior 1800 99mTc-Dimercaptosuccinic Acid Renal SPECT
    J Nucl Med 40: 60-63, 1999
      
    The quality of renal SPECT images can be attenuated by the liver and spleen. This study evaluates whether 1800 SPECT improves image quality over that obtained with a 3600 imaging technique.
      
    Out of 134 patients culled, 2 groups were formed. Group 1 (41 patients) had a normal 99mTc DMSA planar and SPECT image results together with normal blood chemistry results; in group 2 (16 patients) definite cortical defects were visible on planar and SPECT images.
    A anterior 1800, posterior 1800 and 3600 renal SPECT images were obtained. Total data counts, with regions of interest highlighted on coronal and reoriented saggital slices and quantitative assessment of regional activity were made.
      
    Group 1 patients had obvious organ attenuation on the 3600 scans. The total data counts from the posterior 1800 view exceeded those of the anterior 1800 view. The posterior images were more homogenous than either of the other, as also a significantly greater upper to lower pole ratio. In group 2 patients renal defects were seen more clearly on the posterior 1800 SPECT images; the anterior 1800 images gave the worst view.
      
    Only half of the data were provided by the posterior 1800 method, but more uniform appearing kidneys and higher lesion contrast was obtained. The problem of hypoactive poles could also be avoided by using this technique.
        

  • Craig JC, Wheeler DM, et al (The New Children’s Hosp, Sydney, Australia; Univ of Sydney, Australia)
    How Accurate Is Dimercaptosuccinic Acid Scintigraphy for the Diagnosis of Acute Pyelonephrits? A Meta-analysis of Experimental Studies
    J Nucl Med 41: 986-993, 2000
      
    Renal tract imaging with 99mTc DMSA scintigraphy has largely replaced IV urography as a test for assessing renal parenchymal damage from urinary tract infection in children. The role of DMSA scintigraphy has been investigated in the diagnosis of acute pyelonephritis. The standard technique, planar DMSA was compared with SPECT DMSA.
      
    Animal studies comparing DMSA scintigraphy with histopathology were reviewed. Of 7 studies, 2 included SPECT DMSA. Problems in study design and reporting were common. Numerical errors were found in 4 studies. Overall SPECT DMSA had an estimated specificity of 91% at a sensitivity of 86%. The threshold for detecting acute pyelonephritis was lower for SPECT than for planar DMSA.
      
    Applied to a hypothetical group of 100 children with a 40% prevalence of renal damage, 98% of the children with abnormal planar DMSA scans would have renal damage, whereas only 65% of those with abnormal SPECT scans would have renal damage.
      
    Planar and SPECT DMSA would miss 11% and 3% respectively of children with renal damage. In this hypothetical group SPECT would identify 6 additional true cases of renal damage but yield 19 additional false positive results compared with planar DMSA. SPECT DMSA alone does not appear to be preferable to the established planar DMSA.
       

  • Sattari A, Kampouridis S, et al (Hopital Universitaire Saint-Pierre Bruxelles Belgium; Hopital Universitaire des Enfants de la Reine Fabiola, Bruxelles, Belgium)
    CT and 99mTc DMSA Scintigraphy in Adult Acute Pyelonephritis: A Comparative Study
    J Comput Assist Tomogr 24: 600-604, 2000
      
    The role of CT and 99mTc DMSA scintigraphy in the diagnosis of APN (acute pyelonephritis) in adults thought to have urinary tract infection (UTI) have been investigated.
     
    36 patients with UTI underwent plain B-mode sonography, CT scan with contrast and 99mTC DMSA scintigraphy of the kidneys. The latter two were performed within 72 hours after admission.
     
    In 12 patients with clinical and biological signs of UTI, both CT and DMSA scintigraphy were normal. In this group 10 patients had lower UTI and 2 had ureteral obstruction. In the remaining 24 patients APN was diagnosed. In 11 of these patients CT and 99mTc DMSA scintigraphy were correlated.
      
    Findings on both examinations were normal in 2 patients and abnormal in 9. In the remaining 13 patients, 11 had abnormal CT findings but normal scintigraphic findings and 2 had normal CT but abnormal scintigraphic findings.
      
    In 2 patients bilateral lesions detected by CT appeared as unilateral abnormalities on 99mTc DMSA scintigraphy in diagnosing APN lesions.
       

  • Yen T-C, Tzen K-Y, et al (Chang Gung Univ, Taipei, Taiwan; Natl Yang-Ming Univ, Taipei, Taiwan)
    The Value of Ga-67 Renal SPECT in Diagnosing and Monitoring Complete and Incomplete Treatment in Children with Acute Pyelonephritis
    Clin Nucl Med 24: 669-673, 1999
       
    The usefulness if 67Ga Renal SPECT in the diagnosis and monitoring of children with acute pyelonephritis (APN) has been evaluated.
       
    71 children with suspected APN (1 week to 12 years) underwent Renal SPECT scanning within 3 days of hospital admission 99mTc DMSA and 67Ga renal SPECT cystourethrography were done and repeated 3 months after treatment for those with abnormal initial findings.
      
    Lesions were detected on 97% of the 67Ga and 79% of the 99mTc DMSA renal SPECT images. 67Ga renal SPECT also returned 3 false negative results. 17 patients who were positive by the 67Ga SPECT were negative on 99mTc DMSA. 30% of the 107 kidneys had permanent scars, 78% of those were associated with high grade vesicoureteral reflux and 27% with low grade or no vesicoureteral reflux. Posttherapy imaging did not detect 67Ga uptake in any patients.
      
    67Ga renal SPECT presents a more effective diagnosis of APN and enhanced monitoring abilities when compared with 99mTc DMSA renal SPECT. It may also prove more accurate in detecting the extent of vesicoureteral reflux in patients with APN.
        

  • Chan Y-L, Chan K-W, et al (Chinese Univ of Hong Kong, China)
    Potential Utility of MRI in the Evaluation of Children at Risk of Renal Scarring
    Pediatr Radiol 29: 856-862, 1999
      
    The use of MRI in children at risk for renal scarring was assessed by comparing it to technetium 99m-dimercaptosuccinic acid (99mTc-DMSA).
      
    24 children at increased risk for urinary tract infection (UTI) because of spinal dysraphism and neurogenic bladder or anorectal anomaly (18 and 6 children respectively) were assessed. None of them had a history of acute pyelonephritis.
      
    The mean age of the 11 girls and 3 boys was 5.3 years. 10 children had documented UTI and 14 had a history of asymptomatic bacteraemia. Patients underwent 99mTc-DMSA scans and MRI to assess renal scarring. The 99mTc-DMSA scans were supplemented with pin hole imaging. The MRI of the kidneys used a fat saturated T1-weighted sequence and the post-gadolinium STIR sequence used a short echo time.
      
    16 kidneys (33%) showed a renal parenchymal defect indicative of scarring on 99mTc-DMSA. The concordance in detection of a scarred kidney by post-gadolinium STIR sequence and 99mTc-DMSA fat saturated T1-weighted sequence and 99mTc-DMSA and both sequences respectively, had a sensitivity of 94%, 82%, and 100%. With 99mTc-DMSA as the gold standard MRI had a sensitivity and specificity of 100% and 78% respectively, in the diagnosis of a scarred kidney.
      
    Concordance in detection of a scarred zone by post-gadolinium STIR sequence and 99mTc-DMSA fat saturated T1-weighted sequence and DMSA, and both sequences respectively had a sensitivity of 68%, 44% and 84% respectively. With 99mTc-DMSA as the gold standard, the sensitivity and specificity of MRI in the detection of a scarred zone was 84% and 86% respectively.
      

  • Wong DC, Rossleigh MA, et al (Prince of Wales and Sydney Children’s Hosp, Australia)
    Diuretic Renography With the Addition of Quantitative Gravity-Assisted Drainage in Infants and Children
    J Nucl Med 41: 1030-1036, 2000
       
    The use of quantitative gravity assisted drainage using greater than 50% residual activity as an indicator to verify obstruction in diuretic renography in the investigation of hydronephrosis and hydroureteronephrosis in infants and children has been evaluated.
      
    200 children (aged 2 days to 16 years) were studied. In 135 patients diuretic was given 20 minutes after radiopharmaceutical, and in 65 patients, the two were administered simultaneously.
      
    Studies were done with IV administration of technetium 99m-mercaptoacetyltriglycine (99mTc-MAG3) and furosemide. A 5-minute post- gravity-assisted drainage image was obtained after 20 minute diuretic phase. The percentage of residual activity was calculated by comparison with the last 5 minutes of the diuretic phase. All patients were monitored for 6-12 months. The final diagnoses was based on surgical findings or conservative management with follow-up sonography or 99mTc-MAG3 studies.
      
    10 of 256 hydronephrotic renal units showed no function and 1 showed poor function. 131 units had a half life (t1/2) of <10 minutes; 52 units had a half life of 10-20 minutes and 62 units >20 minutes.
       
    Only 1 case of obstruction was found among 131 renal units (t1/2 <10 minutes). Based on gravity assisted drainage exceeding 50% residual activity for diagnosing obstruction in 62 renal units (t1/2 >20 minutes). The sensitivity was 88.4% the specificity 73.7% and the accuracy 83.9%. By using gravity assisted drainage exceeding 50% residual activity for diagnosing obstruction in 52 units with t1/2 of 10-20 minutes, the sensitivity was 100%, the specificity 79.5% and the accuracy of 82.7%.
       
    This test can distinguish between obstruction and non-obstruction in renal units with t1/2 >20 minutes only.
         

  • Clorius JH, Schottler T, et al (Univ of Heidelberg, Germany)
    Afferent-Efferent Vessel Dysfunction Appears to Be a Specific Characteristic of a Large Subset of Patients with Essential Hypertension
    Am J Hypertens 13: 332-339, 2000
        
    Exercise renography distinguishes between exercise mediated renal dysfunction (50%-60%) and non exercise mediated dysfunction. This study aims to find out whether disturbances are also present at rest.
       
    26 patients with essential hypertension (EH) and 21 normotensive persons were assessed with a resting sequential renogram by using technetium 99m (99mTc) mercaptoacetyltriglycine (MAG3). Patients with EH also underwent exercise renography. 3 consecutive 10 minute dual-tracer infusion clearance determinations were made with indium 111-DTA and iodine 131-hippurate to simultaneously determine glomerular filtration rate (GFR) and effective renal plasma flow.
       
    Exercise mediated renal dysfunction developed in 16 of 26 cases of EH. The variability of GFR differed between patients and control subjects. The variability fraction indicated that patients with a bilateral abnormal exercise renogram had a more marked GFR variability than those patients with a normal exercise renogram.
       
    Intraglomerular pressure fluctuations appear to be present in patients with EH. The variable GFR may provoke renin secretion in EH.
       

  • Van de Ven PJG, de Klerk JMH, et al (Univ Med Ctr Utrecht, The Netherlands)
    Aspirin Renography and Captopril Renography in the Diagnosis of Renal Artery Stenosis
    J Nucl Med 41: 1337-1342, 2000
       
    This study compares aspirin versus captopril renography for diagnosis of renal artery stenosis (RAS).
      
    Aspirin and captopril renography were compared prospectively with technetium 99m mercaptoacetyltriglycine (99mTc-MAG3) in 75 consecutive patients suspected of having RAS. Intraarterial digital subtraction angiography was performed on all patients within a month of the last renographic study (50% or more reduction in renal artery diameter was considered positive for RAS).
      
    RAS was identified unilaterally in 34 patients and bilaterally in 17. 24 patients had no evidence of RAS. The sensitivity of captopril renography was 88% for both unilateral and bilateral RAS. For aspirin renography, the sensitivities for unilateral and bilateral RAS were 82% and 94% respectively.
       
    The overall specificity for RAS was 75% for captopril renography and 83% for aspirin renography. There was no significant difference between the two methods in tracer uptake ratios, time to peak activity and percentage of 20 minute tracer retention.
       
    In subgroup analysis of modest and severe RAS and of plasma creatinine >120 mmol/L, no differences were seen. The two methods are almost equal in the diagnosis of RAS.
        

  • Juillard L, Janier MF, et al (Hopital Edouard Herriot, Lyon, France; Hopital Cardiologique, Bron, France; et al)
    Renal Blood Flow Measurement by Positron Emission Tomography Using 15O-Labeled Water
    Kidney Int 57: 2511-2518, 2000
       
    A non-invasive method of determining renal blood flow (RBF) would be valuable. PET with oxygen 15-labeled water (H215O) could be used to non invasively measure RBF. An animal model has been used to validate the measurement of RBF by PET with H215O.
      
    The study was performed on 6 four month old farm pigs. RBI was assessed for each pig with both PET and radioactive microspheres (MS) at baseline during continuous dopamine infusion associated with vascular expansion by hydroxyethyl starch (HES) and isotomic saline and during continuous angiotensin II infusion.
      
    PET and MS were highly correlated over RBF range from 100 to 500 mL/min per gram. Pharmacologically induced changes were assessed equally well by PET and MS.
      
    PET with H215O appears to be a useful non-invasive technique for the measurement of RBF. The limitations are the cost and the PET availability. Benefits include possibility of rapid sequential measurements, comparison between measurements and reduced irradiation.
       

  • Isiklar I, Aktas A, et al (Baskent Univ, Ankara, Turkey)
    From Donor to Recipient: Doppler US, Power US and Scintigraphy of Kidney Perfusion Before and After Transplantation
    Acta Radiol 41: 285-287, 2000
       
    Duplex Doppler US, Power Doppler US and Scintigraphy have been prospectively used to examine kidney perfusion before and after donation to study the changes in perfusion status.
      
    12 donor/recipient pairs were studied. Both kidney donors were studied before surgery with duplex Doppler US, power Doppler US and scintigraphy. Renal allografts were assessed 1 day, 1 month and 3 months postoperatively. Multiple resistance indices were calculated, based on interlobar and segmental artery flow. All patients in the study group had normal kidney function.
      
    In the normally functioning kidneys postoperatively after 1 month, the intrarenal resistance and after 3 months there was a decrease in renal artery peak systolic velocity.
        

  • Russell CD, Yang H, et al (Univ of Alabama, Birmingham; Shanxi Med Univ, Taiyuan, China)
    Prediction of Renal Transplant Survival From Early Postoperative Radioisotope Studies
    J Nucl Med 41: 1332-1336, 2000
      
    A 3-day postoperative (renal transplant) study is usually performed – imaging, estimation of effective plasma renal flow (ERPF) from a simple plasma sample. The co-relation between baseline measurements and 1-year graft survival have been presented.
       
    In 1998 iodine 131-orthoiodohippurate (OIH) was used and in 1995 technetium-99m-mercaptoacetylglycine (99mTc-MAG3) was used. Previously published single injection single sample methods were used in the concurrent measurement of ERPF and gamma camera imaging by converting MAG3 clearance to ERPF by means of a correction factor.
      
    Graft survival in the first postoperative year was significantly improved in the interval between the cohort years (1988 and 1995) from 74% of 146 cadaver grafts in 1988 to 91% of 200 cadaver grafts in 1995.
      
    However there was no significant change for living related donors (LRD) grafts which were successful for 91% of 66 (1988) and 91% of 83 (1995). In both cohort years the baseline ERPF was a significant predictor of graft survival. The association was not significant for LRD grafts in either cohort. In the 1995 cohort, the peak time and ratio of counting rate at 20 minutes to that at 3 minutes (R20:3) were also found to be significant predictors for cadaver graft survival.
       
    In the 1988 cohort the correlation with peak time was not significant, and the 
    the R20:3 measurement was not available. Simple sample ERPF in the immediate post transplant period whether from OIH clearance or MAG3 clearance is a significant predictor of graft survival for cadaver transplants. Peak time and R20:3 were also found to be significant predictors for MAG3. However these associations are not valid for LRD transplants.
        

 

 

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