Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Selecting the appropriate approach for resection and follow-up of pheochromocytomas (PCCs) is highly dependent upon reliable localization and exclusion of multifocal, bilateral, or metastatic disease. Metaiodobenzylguanidine (MIBG) scintigraphy was developed for functional localization of catecholamine-secreting tissues. Somatostatin receptor imaging (SRI) has a high sensitivity for localizing head and neck paragangliomas, but studies of intraabdominal PCCs are rare. In this study we review our experience of [(123)I]MIBG and SRI, performed since 1983 and 1989, respectively, in the work-up of primary and recurrent PCCs. Scintigraphic results were correlated with catecholamine secretion, size and site, malignancy, associated tumor syndromes, and morphological features. [(123)I]MIBG scans were performed in a total of 75 patients, in 70 cases before resection of primary PCCs and in 5 cases because of recurrent disease. Ninety-one PCCs were resected. The overall detection rates were 83.3% and 89.8% for PCCs larger than 1.0 cm. Multifocal disease was detected in 4 patients with [(123)I]MIBG. [(123)I]MIBG uptake correlated with greater size of PCC (r = 0.33; P = 0.008) and greater concentration of plasma epinephrine (r = 0.32; P = 0.006). [(123)I]MIBG-negative PCCs (n = 14) had significantly (P = 0.01) smaller diameters than [(123I)]MIBG-positive tumors. Furthermore, [(123)I]MIBG uptake was significantly higher in unilateral (P = 0.02), benign (P = 0.02), sporadic (P = 0.02), intraadrenal (P = 0.02), and capsular invasive (P = 0.03) PCCs than in bilateral, malignant, MEN2A/2B-related, extraadrenal, and noninvasive PCCs, respectively. The detection rate of SRI was only 25% (8 of 32) for primary benign PCCs. In 14 patients metastases occurred, which were effectively visualized with [(123)I]MIBG in 8 of 14 cases. SRI was able to detect metastases in 7 of 8 cases, including 3 [(123)I]MIBG-negative metastatic cases. In addition, [(123)I]MIBG and SRI detected 2 recurrences. In conclusion, [(123)I]MIBG uptake is correlated with the size, epinephrine production, and site of PCCs. Its role in bilateral and MEN2A/2B-related PCCs seems limited. In cases of recurrent elevation of catecholamines, localization of metastases and/or recurrence should be attempted with [(123)I]MIBG scintigraphy. In suspicious metastatic PCCs, SRI might be considered to supplement [(123)I]MIBG scintigraphy.
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PMID:[(123)I]metaiodobenzylguanidine and [(111)In]octreotide uptake in begnign and malignant pheochromocytomas. 1115 32

This is a consensus statement from an international group, mostly of clinical endocrinologists. MEN1 and MEN2 are hereditary cancer syndromes. The commonest tumors secrete PTH or gastrin in MEN1, and calcitonin or catecholamines in MEN2. Management strategies improved after the discoveries of their genes. MEN1 has no clear syndromic variants. Tumor monitoring in MEN1 carriers includes biochemical tests yearly and imaging tests less often. Neck surgery includes subtotal or total parathyroidectomy, parathyroid cryopreservation, and thymectomy. Proton pump inhibitors or somatostatin analogs are the main management for oversecretion of entero-pancreatic hormones, except insulin. The roles for surgery of most entero-pancreatic tumors present several controversies: exclusion of most operations on gastrinomas and indications for surgery on other tumors. Each MEN1 family probably has an inactivating MEN1 germline mutation. Testing for a germline MEN1 mutation gives useful information, but rarely mandates an intervention. The most distinctive MEN2 variants are MEN2A, MEN2B, and familial medullary thyroid cancer (MTC). They vary in aggressiveness of MTC and spectrum of disturbed organs. Mortality in MEN2 is greater from MTC than from pheochromocytoma. Thyroidectomy, during childhood if possible, is the goal in all MEN2 carriers to prevent or cure MTC. Each MEN2 index case probably has an activating germline RET mutation. RET testing has replaced calcitonin testing to diagnose the MEN2 carrier state. The specific RET codon mutation correlates with the MEN2 syndromic variant, the age of onset of MTC, and the aggressiveness of MTC; consequently, that mutation should guide major management decisions, such as whether and when to perform thyroidectomy.
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PMID:Guidelines for diagnosis and therapy of MEN type 1 and type 2. 1205 Feb 90