Long term use of metformin in idiopathic cyclic edema, report of thirteen cases and review of the literature.

INTRODUCTION: Idiopathic cyclic edema (ICE) is a rare cause of edema. To date, there is no standard of care. The physiopathology of ICE could be explained by an impairment of capillary permeability. In 1995, a study demonstrated the efficacy of metformin on symptoms and capillary permeability. We evaluated ICE-patients who were treated with metformin in our department. METHODS: We retrospectively included patients diagnosed for ICE between January 1997 and October 2013. ICE was diagnosed in the presence of edema after excluding other etiologies. LANDIS test was used to support ICE diagnosis in all patients. The absence of edema at follow-up was considered as complete response (CR), partial decreased was considered as partial response (PR). Adverse events were recorded. RESULTS: Thirteen patients have accepted to use metformin. The median treatment duration was 28.5 months [8-167] and the median follow-up of treated patients was 40.5 months [14-167]. CR was reached in 10 patients (77%), and PR in 2 patients (15%). Two patients reported side-effects as diarrheas and one of them stopped the treatment due to mild diarrhea. CONCLUSION: We report the interest and tolerance of the long-term use of metformin in ICE. No severe adverse events were noticed. A prospective study is needed to confirm the efficacy of metformin in ICE-patients.

Radioimmunotherapy ((90) Y-Ibritumomab Tiuxetan) for Posttransplant Lymphoproliferative Disorders After Prior Exposure to Rituximab.

Posttransplantation lymphoproliferative disorders (PTLDs) are life-threatening complications after solid organ and hematopoietic stem cell transplantation. Only half of CD20-positive PTLDs respond to rituximab monotherapy, and outcomes remain poor for patients with relapsed/refractory disease, especially those who do not qualify for an anthracycline containing regimen due to frailty or comorbidities. Radioimmunotherapy (RIT) might be an option in this particular setting. We report a panel of eight patients with rituximab refractory/relapsed CD20-positive PTLDs including three ineligible for subsequent CHOP-like chemotherapy who received (90) Y-Ibritumomab tiuxetan as a single agent (n = 7) or combined to chemotherapy (n = 1). Five out of eight patients were kidney transplant recipients, while 2/8 had a liver transplant and 1/8 had a heart transplant. Patients received a median of two previous therapies. Overall response rate was 62.5%. Importantly, all responders achieved complete response. At a median follow-up of 37 months [5; 84], complete response was ongoing in four patients. Toxicity was predominantly hematological and easily manageable. No graft rejection was noticed concomitantly or following RIT administration despite immunosuppression reduction after diagnosis of PTLDs. This report emphasizes the potential efficiency of salvage RIT for early rituximab refractory PTLDs without any unexpected toxicity.

FDG-PET in the assessment of patients with follicular lymphoma treated by ibritumomab tiuxetan Y 90: multicentric study.

BACKGROUND: The aim of this study is the 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) evaluation following radioimmunotherapy (RIT) with ibritumomab tiuxetan Y 90 in patients with non-Hodgkin's follicular lymphoma (FL). MATERIALS AND METHODS: We retrospectively analyzed data from 59 relapsed or refractory FL patients treated with ibritumomab tiuxetan Y 90 in four different PET centers who had a PET scan carried out before and after RIT. Possible predictive factors of progression-free survival (PFS) were studied through univariate and multivariate analysis. RESULTS: The post-RIT PET documented 45.8% complete responders (CR), 25.4% partial responders (PR) and 28.8% nonresponders [stable disease + progressive disease], with an overall survival of 71.2% (range 59.5%-90.9%). With a median follow-up period of 23 months, the univariate analysis documented a statistically significant relation between disease extent before RIT and response to treatment with respect to PFS (P = 0.015), while all the other prognostic factors showed no significant correlation. When carrying out the multivariate analysis, post-RIT PET resulted as the lonely independent predictor of PFS (P < 0.00001). CONCLUSIONS: RIT is an effective therapy in FL patients, as confirmed in our study too. Disease extension before treatment and response to RIT, as assessed by FDG-PET, result as main predictors of PFS, with the post-RIT PET result being the only independent predictive factor.

An easy-to-use phantom and protocol for weekly PET quality assessment: a multicenter study.

The authors have developed a simple phantom and dedicated software for the quality assessment of positron emission tomography (PET) scanners. The phantom is a parallelepiped box filled with a relatively low activity 18FDG solution and in which simple test objects are placed. Various image quality parameters are checked, including signal-to-noise ratio, image uniformity, slice thickness, slice sensitivity profile, spatial resolution, and dose calibration accuracy. Automatic image analysis consists in detecting surfaces and objects, defining regions of interest, acquiring reference point coordinates, and establishing gray-scale profiles. The total time needed for quality assessment (preparation and image acquisition) is less than 15 min with 37 MBq (1 mCi) 18FDG. The system's ease of use encourages frequent image quality assessment-for example, the comparison of PET scanners in interdepartment studies and the monitoring and evaluation of possible drifts over time. By way of an example, the authors present weekly quality assessment results obtained over up to 7 months at four PET facilities.

A new pharmacokinetic model for 90Y-ibritumomab tiuxetan based on 3-dimensional dosimetry.

Monoclonal antibodies (mAbs) are key components in several therapies for cancer and inflammatory diseases but current knowledge of their clinical pharmacokinetics and distribution in human tissues remains incomplete. Consequently, optimal dosing and scheduling in clinics are affected. With sequential radiolabeled mAb-based imaging, radiation dosing in tissues/organs can be calculated to provide a better assessment of mAb concentrations in tissues. This is the first pharmacokinetic model of 90Y-Ibritumomab tiuxetan (90Y-IT) in humans to be described, based on three-dimensional (3D) dosimetry using single-photon emission computed-tomography coupled with computed-tomography. 19 patients with follicular lymphoma were treated initially with 90Y-IT in the FIZZ trial. Based on a compartmental approach individualising the vascular compartment within studied organs, this study proposes a reliable pharmacokinetic (PK) five-compartment model replacing the currently used two-compartment model and constitutes a new direction for further research. This model provides exchange constants between the different tissues, Area Under the Curve of 111In-IT in blood (AUC) and Mean Residence Time (MRT) that have not been reported so far for IT. Finally, the elimination process appears to occur in a compartment other than the liver or the spleen and suggests the metabolism of mAbs may take place mainly on the vascular compartment level.

[Usefulness of nuclear medicine in Erdheim-Chester disease: A Lille experience]. / Intérêt de la médecine nucléaire dans la maladie d'Erdheim-Chester : une expérience lilloise.

INTRODUCTION: Erdheim-Chester disease is a rare form of non-langerhans histiocytosis and its etiology is still not well established. The aims of the study were to assess the value of the bone scintigraphy and the 18F-FDG PET/CT for the diagnostic and for the latter in the therapeutic evaluation. METHODS: We retrospectively reviewed 49 patients suspected of Erdheim-Chester disease between 2004 and 2016. Bone scintigraphy was compared with histopathology and PET-CT to conventional morphological examinations and bone scintigraphy. For therapeutic evaluation, thresholds similar to PERCIST 1.0 were used. RESULTS: Forty-nine bone scintigraphy were evaluated with a sensitivity of 100%, a specificity 97%, a positive predictive value 90% and a negative predictive value of 100%. Eight patients had at least an initial PET-CT. The sensitivity compared to conventional morphological examinations differed from the location but was excellent for orbital, bone and vascular involvements. Specificity was comparable between the different examinations. Six patients treated with interferon® and three with vemurafenib® were followed by PET-CT. PET-CT, in agreement to clinicobiological data, identified 4 partial responses and one complete response with interferon® et two partial responses and one complete response with vemurafenib®. CONCLUSION: Our retrospective study suggests that bone scintigraphy and 18F-FDG PET/CT could be useful in the initial assessment of Erdheim-Chester disease but also for the latter in the therapeutic evaluation.

[Positron emission tomography: current use in internal medicine and future perspectives]. / La tomographie d'émission de positons en médecine interne: applications actuelles et perspectives d'avenir.

PURPOSE: Fluorodeoxyglucose positron emission tomography (FDG-PET) is a promising imaging technique that has already proven effective in modifying patient care in oncology. Fluorodeoxyglucose still remains the main radiopharmaceutical agent routinely used for PET imaging. A growing interest has recently lead to broaden PET research on benign disorders. The field of inflammatory or immune diseases and globally the field of internal medicine could also be impacted by FDG-PET. MAIN POINTS: Great vessels vasculitides and fever of unknown origin have both been studied by several teams and could become indications for PET. In addition, current indications now extend to paraneoplastic syndromes. It is thus possible to foresee that the clinical applications for PET will continue to expand in these patients. PERSPECTIVES AND PROJECTS: In the future, inflammatory arthritis, chronic inflammatory bowel diseases, systemic erythematous lupus, histiocytosis, or pulmonary and retroperitoneal fibrosis might benefit from PET even if, available data remains scarce to this day. Although PET will probably alter the landscape of patient management in internal medicine in the near future, additional clinical research is still needed to ascertain the exact role of PET.

[18FDG PET: a new criterion for disease activity in Takayasu arteritis]. / La TEP au 18FDG au cours de l'artérite de Takayasu: un marqueur d'activité de la maladie.

INTRODUCTION: Takayasu arteritis (TA) is an inflammatory arteritis affecting large vessels, predominantly the aorta, its main branches, and the pulmonary arteries. Up to now, arteriography was considered as the "gold standard". But others exams are emerging in the management of TA: vascular ultrasound, angio-scanner, magnetic resonance imaging and 18FDG positron emission tomography (18FDG PET). Such investigations allow a study of the lumen but also of the arterial walls. However, at the time, no biological or radiological test is able to determine the activity of TA. 18FDG PET could be effective to estimate the disease activity. EXEGESIS: We report the case of a young woman for who 18FDG PET permit to assert a relapse of TA. CONCLUSION: 18FDG PET could be effective to estimate the disease activity.

[Are preoperative examinations useful in the management of patients with renal hyperparathyroidism?]. / L'imagerie préopératoire des hyperparathyroïdies des insuffisants rénaux a-t-elle un intérêt en pratique clinique?

AIM OF THE STUDY: To evaluate the efficiency of preoperative parathyroid ultrasonography and scintigraphy in the management of renal hyperparathyroidism. PATIENTS AND METHODS: The charts of the last consecutive 200 patients who underwent surgery for renal hyperparathyroidism from 1998 to 2003 were retrospectively reviewed to collect data concerning parathyroid gland function, results of preoperative ultrasonography and scintigraphy, as well as modalities and results of surgical exploration. RESULTS: Ultrasonography and scintigraphy sensibilities were 36.4% and 49.3%, respectively. Efficiency of both examinations was improved when they were combined (sensibility of 64.7%) and in those patients managed for recurrent hyperparathyroidism. Were more often detected by preoperative examinations glands with high weight and/or greatest diameter, orthotopic and inferior glands as well as glands exhibiting nodular hyperplasia content upon pathological examination. CONCLUSION: Parathyroid ultrasonography and scintigraphy are of poor interest in the management of renal hyperparathyroidism. In a preoperative setting, they should be performed only in patients with recurrent disease.

Comparison between Leukoscan (Sulesomab) and Gallium-67 for the diagnosis of osteomyelitis in the diabetic foot.

OBJECTIVES: The diagnosis of osteomyelitis in patients with diabetic foot is difficult both clinically and radiologically. An early diagnosis is crucial to optimize therapeutic strategy. Among the diagnostic methods currently used, scintigraphy with ex-vivo labelled white blood cells is the gold standard, but cannot be performed in all centers; therefore 67Gallium citrate (67Ga) imaging in combination with a bone scintigraphy is still widely used. METHOD: The results of imaging 24 diabetic patients with 31 suspected osteomyelitic lesions using the antigranulocyte Fab' fragment (Sulesomab or LeukoScan or immunoscintigraphy) were prospectively compared with results from the bone scan coupled with 67Ga. The diagnosis of osteomyelitis was confirmed by either biopsy or follow-up, radiological imaging and clinical outcome. RESULTS AND CONCLUSION: Sulesomab correctly identified 12 of 18 osteomyelitic lesions while 67Ga was able to detect only 8 of 18. Therefore the sensitivity is 67% for Sulesomab and 44% for 67Ga. Among the 13 non-osteomyelitic lesions imaging with Sulesomab was able to rule out infection in 11 cases and 67Ga in 10 cases. The specificity is therefore 85% for Sulesomab and 77% for 67Ga. Image interpretation for Sulesomab in this group of patients is occasionally suboptimal when imaging is performed at 3 hours post injection. High vascular background in the early images may obscure infection especially in small bones. Practically, scintigraphy with Sulesomab is fast and simple due to ease of labeling, no ex-vivo handling of blood, low radiation and provides rapid diagnosis. The diagnosis of osteomyelitis obtained by the antibody fragment scintigraphy influences the management (guided biopsy) and therapy. In several patients, imaging with Sulesomab was able to rule out osteomyelitis, helping to avoid useless antibiotic therapy and its associated side effects.

[Paragangliomas: clinical and secretory profile. Result of 39 cases]. / Paragangliomes: profil clinique et sécrétoire. A propos de 39 cas.

THIS RETROSPECTIVE STUDY AIMS: To define a clinical and secretory profile of paragangliomas extra-adrenal chromaffin tumors. METHODS: From 1971 throughout 2002, 39 paragangliomas have been observed in 38 patients (22 male, 16 female, average age 41,2 years). RESULTS: Four were located above the diaphragm, 35 were sub-phrenic (6 of the organ of Zuckerkandl), 32 secreted catecholamines, 23 were hypertensive (with only one without hypersecretion of catecholamines). Among 29 (131)I-metaiodobenzylguanidine scans (MIBG) reviewed, 20 tumors took up the radiopharmaceutical. The treatment was surgical in 35 cases with addition of external radiotherapy and MIBG in one case each; two patients died before any treatment. Two patients with persistent disease after surgery were successfully treated by surgery or MIBG. Histologically, 20 were malignant and 17 were seemingly benign. All exclusive dopamine secreting paragangliomas were malignant. Six patients relapsed two of which for a tumor initially classified as benign. The treatment of recurrences was surgical, by MIBG or by external radiotherapy. Nine patients had a family history of chromaffin tumor(s). The genetic survey made in five of these nine patients was positive in all cases.

Regional cerebral blood flow imaging: a quantitative comparison of 99mTc-bicisate with 133Xe using single photon emission computed tomography.

The aim of this study was to compare 99mTc-bicisate with 133Xe inhalation in regional CBF (rCBF) imaging. Five healthy volunteers and five patients were imaged with both techniques. Regional standardized values (SVs) of 99mTc-bicisate, uptake indexes (UIs), and asymmetry indexes (AIs) were compared quantitatively with, respectively, rCBF, flow indexes (FIs), and AIs. Areas with highest rCBF (sylvian and thalamic areas) appeared to be underestimated with 99mTc-bicisate, but significant correlations were found between SV and rCBF (n = 140, r = 0.468, p < 0.01) and for the 10 subjects between UI and FI and between AIs (p < 0.0001). There are therefore distinct regional differences in the cerebral distinction of 99mTc-bicisate and CBF, particularly in the thalamus and the temporal cortex. It is probable but not yet proved that an underestimation of high flow rates occurs with bicisate.

Prospective and serial study of primary amyloidosis with serum amyloid P component scintigraphy: from diagnosis to prognosis.

OBJECTIVE: The purpose of this study was to assess the value of the serum amyloid P (SAP) component scintigraphy in patients with primary amyloidosis (AL). MATERIAL AND METHODS: Pure human SAP labeled with iodine-123 (123I-SAP) was given intravenously to 24 patients with biopsy-proven systemic amyloidosis (15 without multiple myeloma = group 1, and 9 with multiple myeloma = group 2) and to 6 patients with multiple myeloma without any clinical or biological signs of amyloidosis (group 3). Whole-body images as well as regional views and tissue retention levels were obtained after 24 hours. Our study was approved by the institutional review committee and all individuals gave informed consent and were prospectively studied (median 13 months, range 1 to 47 from the date of the scintigraphy to May 1995). RESULTS: Organ localization of 123I-SAP, indicating the presence of substantial visceral amyloid deposits, was observed in all patients in group 1 and 2. The organ uptake of 123I-SAP included the spleen (1 patient was splenectomized) in 20 of 23 cases (87%), the liver in 15 of 24 (60%), and the kidneys in 6 of 24 (25%). Myocardial 123I-SAP was never seen although 13 out of the 24 patients had clinical or echographic data for amyloidosis. Twenty-four hour tissue retention was significantly elevated in all patients (group 1 and group 2): 55.66% +/- 19.16% in group 1 and 34.37% +/- 24.92% in group 2, as compared with normal levels < 24%. The sensitivity of the technique was 79% when only organ uptake was considered but reached 100% when tissue retention was also considered. The 24-hour tissue retention might be correlated with the severity of the amyloidosis: mean survival in patients with tissue retention greater than 50% was 11.3 months versus 24.5 months in patients with levels less or equal to 50%. Five of the 6 patients with multiple myeloma without evidence of amyloidosis had abnormal 123I-SAP imaging and 24-hour tissue retention levels. In 2 of them, amyloidosis was secondly detected. In the 9 patients who had two scintigraphies, variations in 24-hour tissue retention values were in accordance with the clinical evaluation. CONCLUSIONS: Spleen and liver distribution of amyloidosis is mostly revealed by 123I-SAP scintigraphy in patients with AL amyloidosis. The uptake of 123I-SAP appeared in proportion to the quantity of amyloidosis present in different tissues, and the relative quantity of amyloid deposits in the myocardium, carpal tunnel, digestive tract, and kidneys was often small and seldom visualized by 123I-SAP scintigraphy. In contrast 24-hour tissue retention levels were abnormal in all cases of known AL amyloidosis. This may be a positive argument for the diagnosis of amyloidosis when histopathological tests are normal. Tissue retention levels appear important as they may be correlated with survival.

Factor analysis of dynamic series (FADS) in somatostatin receptor imaging.

UNLABELLED: The aim of this article was to study the physiopathology of tumoral uptake of 111In-pentetreotide using factorial analysis of dynamic series (FADS) and to assess the usefulness of this analysis in somatostatin receptor scintigraphy. METHODS: Forty-one patients were included, 24 women and 17 men. After intravenous injection of 111 MBq 111In-pentetreotide, dynamic image acquisition (68 images of 30 s) began in front of the suspected tumoral site: thoracic in 10 patients with medullary carcinoma of the thyroid and 2 patients with bronchogenic carcinoid, and abdominal in 12 cases of midgut carcinoid and 17 cases of other gastroenteropancreatic neuroendocrine tumors. FADS was performed with FAMIS software. Static images were obtained 4 h and 24 h later. For every patient, surgery and/or clinical follow-up (4 y) was used to classify results as true (T) or false (F) positive (P) or negative (N) and to evaluate both the sensitivity of static images and the usefulness of FADS. RESULTS: Of the 14 cases of carcinoid tumor, 5 patients were TN; 9 patients were TP with static images but only 8 were TP with FADS (a bronchogenic carcinoid of 6 mm was missed). Of the 17 cases of gastroenteropancreatic neuroendocrine tumor, static images were TP in 9 patients, and FADS were TP in 5 of these patients (and 4 FN). Static images and FADS were FN in 4 patients and TN in 3 patients, and in the 2 last patients static images were FP, but FADS were TN. Of the 10 cases of medullary carcinoma of the thyroid, static images and FADS were TN in 1 patient, static images were TP in 3 patients and FADS were TP in 2 of these patients (and 1 FN). In the six last cases, static images were FN, but FADS were FN in 3 patients and TP in 3 patients, showing an infiltrate. CONCLUSION: FADS demonstrates that tumoral kinetics are similar to those of the spleen. FADS can show a diffuse tumoral uptake corresponding to tumoral infiltrate in medullary carcinoma of the thyroid or in hepatic miliaria, whereas static images were normal or doubtful.

Iodine-123-Tyr-3-octreotide uptake in pancreatic endocrine tumors and in carcinoids in relation to hormonal inhibition by octreotide.

UNLABELLED: Uptake of 123I-Tyr-3-octreotide (TOCT) by hormone-secreting abdominal tumors was studied to compare scintigraphic observations with the reduction in hormone levels brought about by a brief therapeutic test. METHODS: A prospective study was conducted on 17 patients, totalizing 46 proven lesions, with endocrine tumors of the pancreas (10 patients, 20 lesions) and/or carcinoid metastases (8 patients, 26 lesions). Tumor hormonal hypersecretion was inhibited by octreotide. RESULTS: There was good agreement between the results of these examinations. CONCLUSIONS: The detection of abdominal tumors using this radiotracer is strongly related to its functional characteristics. Variations in the scintigraphic and test results according to different tumor types were in agreement with published data on the density of somatostatin receptors measured by in vitro studies or scintigraphy and by the therapeutic effects of octreotide.

Chromogranin A assay and (131)I-MIBG scintigraphy for diagnosis and follow-up of pheochromocytoma.

UNLABELLED: We assessed the performance of a new serum chromogranin A (CgA) assay in combination with the results of (131)I-metaiodobenzylguanidine (MIBG) scintigraphy for diagnosis and follow-up in 89 patients with clinical findings suggestive of pheochromocytoma. METHODS: The study population consisted of 41 patients with proven pheochromocytoma and 48 patients with refuted pheochromocytoma. Eighty-seven scintigraphy examinations were performed, 52 in patients with proven pheochromocytoma (39 before surgery and 13 after surgery) and 35 in patients with refuted pheochromocytoma. RESULTS: The sensitivity of the CgA level was 90.2%, and the specificity was 99.0% and 92.3% in the control and refuted pheochromocytoma groups, respectively. A significant relationship was seen between serum levels of CgA and tumor mass (r = 0.70; P < 10(-5)). The postoperative CgA level was an early and accurate predictor of curative surgery or relapse. The concordance between CgA levels and scintigraphic data was 90.8%. CONCLUSION: Serum CgA level is an effective marker of pheochromocytoma. Increased levels strongly correlate with tumor mass; therefore, small tumors may go undetected. The concordance between CgA level and the results of (131)I-MIBG scintigraphy is high. A CgA level in the reference range is highly predictive of normal scintigraphy findings.

Radioimmunodetection of medullary thyroid carcinoma using indium-111 bivalent hapten and anti-CEA x anti-DTPA-indium bispecific antibody.

UNLABELLED: Pretargeting labeled bivalent hapten with bispecific antibodies has proven feasible in the clinic, and our earlier results have suggested the technique may be very sensitive for detecting small recurrences and metastases. Medullary thyroid carcinoma (MTC) is an example where this technique may be the most useful since local recurrences and isolated metastases are removed surgically when detected, and thyrocalcitonin provides a specific and sensitive tumor marker. In our current study, we evaluated pretargeted immunoscintigraphy in a larger number of MTC patients. METHODS: Anti-carcinoembryonic antigen (CEA) x anti-diethylenetriaminepentaacetic acid (DTPA) indium bispecific antibody and 111In-labeled bivalent DTPA hapten were administered sequentially (4-5 days apart) to 44 patients with elevated circulating calcitonin after resection of primary MTC. Immunoscintigraphy was performed 2, 5 and 24 hr after hapten injection and, when necessary, at longer time intervals. When available, a handheld gamma probe was used during surgery. RESULTS: Fifteen patients had known tumor sites before immunoscintigraphy. Tumors were imaged in 12 (80%) of these patients, including 3 with liver metastases. Five unknown tumor sites were detected. For the 29 patients with occult disease, immunoscintigraphy detected high-activity uptake sites in 21 patients (72%), including 5 in the liver. Twelve were confirmed by surgery, 1 by guided morphologic imaging and 1 by venous catheterization. There were 2 false-positive patients. The other 5 patients have not yet been confirmed. All detected liver metastases were high-activity uptake areas. Radioimmunoguided surgery was used in 14 patients. It was considered helpful by the surgeon in 12 patients, including 4 patients where it determined the resection of small, not palpable nor visible, tumor-involved lymph nodes. Surgical resection resulted in a significant decrease (8 patients) or normalization (1 patient) of circulating calcitonin and CEA. CONCLUSION: This technique affords high sensitivity and specificity for detecting small tumor lesions including liver metastases. Its use for immunoscintigraphy and guided surgery should improve the therapeutic management of recurrent MTC.

Scintiscans and carcinoid tumors.

BACKGROUND: The presence of somatostatin receptors on carcinoid tumors mediates imaging of tumor extent and inhibition of tumor growth and marker secretion. This prospective study aimed to evaluate radiolabeled somatostatin analog scans in the therapeutic workup of carcinoids. METHODS: Twenty-one patients with carcinoids underwent 26 scans with iodine octreotide or indium pentetreotide. The results for tumor and metastases imaging were analyzed and compared with those of a short inhibition test of marker secretion and with those of metaiodobenzylguanidine scan. RESULTS: The sensitivity for obtaining images of the overall 43 tumor sites was 72%. We had no false-positive results. Unknown tumor sites were discovered in three patients. The results were slightly better with indium pentetreotide and metastases imaging. A positive scan did not always preclude responsiveness to the functional effect of octreotide. Results of somatostatin analog scans were better than those with metaidobenzylguanidine. The two techniques were complementary in one patient. CONCLUSIONS: The choice of treatment for patients with carcinoid tumors should benefit from functional inhibition test with octreotide and from indium pentetreotide and metaidobenzylguanidine scans.

Correlation of parathyroid scanning and anatomy in 261 unselected patients with sporadic primary hyperparathyroidism.

BACKGROUND: Despite abundant literature on parathyroid scanning with technetium 99m-labeled cationic complexes, comprehensive clinical reports that unequivocally correlate scanning findings with the anatomy of parathyroid glands in extensive and homogeneous cohorts of patients are lacking. METHODS: We analyzed the records of patients with sporadic primary hyperparathyroidism who had had a preoperative scan with either 99mTc-labeled sestamibi or 99mTc-labeled tetrofosmin at our institution and who were cured after a bilateral surgical neck exploration procedure. RESULTS: In 261 patients, 710 normal and 347 abnormal glands (1494 +/- 2626 mg), including 15 glands within the mediastinum, were identified. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of scanning were 82%, 98%, 91%, 94%, and 94%, respectively, in 197 patients with uniglandular disease and 53%, 98%, 98%, 60%, and 72%, respectively, in 64 patients with multiglandular disease. False-positive uptakes were encountered in 17 patients (7%), 3 false-positive uptakes being within the mediastinum. If the unilateral approach had been followed, guidance with preoperative scanning would have significantly increased the number of effective unilateral neck exploration procedures (164 patients (63%) vs 78 patients (30%); P < .001). One abnormal gland would also have been neglected in 28 patients (11%). CONCLUSIONS: Preoperative scanning would limit neck exploration procedures in two thirds of patients with sporadic primary hyperparathyroidism but may also increase the risk of failure in the most challenging cases.

Noninvasive imaging of insulinomas and gastrinomas with endoscopic ultrasonography and somatostatin receptor scintigraphy.

BACKGROUND: Classic morphological techniques are of limited value for imaging endocrine duodenopancreatic tumors, and invasive procedures such as intraarterial stimulation are often used. Two noninvasive procedures, endoscopic ultrasonography (EUS) and somatostatin receptor scintigraphy (SRS), were recently described with promising results. METHODS: In this study we correlated the results of preoperative EUS (n = 34) and SRS (n = 30) with operative findings in patients with histologically proven insulinoma (n = 20) or gastrinoma (n = 21). RESULTS: The sensitivity and positive predictive value (PPV) of EUS were respectively 77% and 94% for pancreatic tumors (insulinomas and gastrinomas), 40% and 100% for duodenal gastrinomas, and 58% and 78% for metastatic lymph nodes. The sensitivity and PPV of SRS for insulinoma were 60% and 100%, respectively. In patients with gastrinoma, the sensitivity and PPV of SRS were respectively 25% and 100% for pancreatic gastrinomas, 72% and 100% for duodenal gastrinomas or periduodenal metastatic lymph nodes, and 67% and 80% for liver metastasis. In patients with multiple endocrine neoplasia, neither one of the two techniques detected all tumors. Overall sensitivity of combined EUS and SRS was 89% for insulinoma (n = 9) and 93% for gastrinoma (n = 14). CONCLUSIONS: EUS and SRS for gastrinomas and insulinomas should be considered as the initial preoperative imaging procedures and may render invasive procedures unnecessary for most patients.