INTRAOPERATIVE LOCALIZATION OF GUT ENDOCRINE TUMORS WITH RADIOLABELEDSOMATOSTATIN ANALOGS AND A GAMMA-DETECTING PROBE

Gut endocrine tumors are sometimes difficult to localize by radiologic al techniques. Carcinoids and gastrinomas, however, possess high densi ty of somatostatin receptors, thus, scintigraphy with radiolabeled som atostatin analogs may prove useful for detection of occult gastroenter opancreatic endocrine tumors when conventional diagnostic methods fail . A novel method of radioguided surgery with a hand-held gamma-detecti ng probe (GDP) has been used to localize gut endocrine tumors by bindi ng radiolabeled somatostatin analogs. We also applied the method in a patient with occult carcinoid: after injecting 125-Iodine (I-125)-octr eotide intraoperatively, we obtained accurate localization of the jeju nal carcinoid and of a liver metastasis previously undetected. Sevente en cases of gut endocrine tumors detected by this technique that have been reported in the literature are reviewed and discussed. Intraopera tive localization of gastrointestinal endocrine tumors with radiolabel ed somatostatin analogs and a GDP expands the possibility of accurate tumor detection one step beyond that obtained by conventional imaging and by intraoperative inspection and palpation. Semin. Surg. Oncol. 15 :239-244, 1998. (C) 1998 Wiley-Liss, Inc.