BACKGROUND: An occult insulinoma refers to a biochemically proven tumor with an anatomic site that remains indeterminate before operation. The amount of radiologic localization for such patients is debatable. METHODS: Sixty-five patients with sporadic insulinomas were surgically treated at the Mayo Clinic between January 1980 and December 1990. True occult tumors were present in 31% of these patients (n = 20). Thirty-eight negative preoperative localization studies were performed, with 10 patients undergoing more than one study. A benign adenoma was found in 19 patients when they underwent exploratory operation, whereas one patient had malignant disease with hepatic metastases. Thirteen patients underwent intraoperative ultrasonography with a 7.5 MHz real-time high-resolution transducer. RESULTS: Solitary lesions were successfully removed either by enucleation or by distal pancreatectomy in all 19 patients with benign disease. CONCLUSIONS: This high success rate in the management of occult insulinomas suggests that extensive preoperative radiologic investigation is neither indicated nor cost-effective.
BACKGROUND: An occult insulinoma refers to a biochemically proven tumor with an anatomic site that remains indeterminate before operation. The amount of radiologic localization for such patients is debatable. METHODS: Sixty-five patients with sporadic insulinomas were surgically treated at the Mayo Clinic between January 1980 and December 1990. True occult tumors were present in 31% of these patients (n = 20). Thirty-eight negative preoperative localization studies were performed, with 10 patients undergoing more than one study. A benign adenoma was found in 19 patients when they underwent exploratory operation, whereas one patient had malignant disease with hepatic metastases. Thirteen patients underwent intraoperative ultrasonography with a 7.5 MHz real-time high-resolution transducer. RESULTS: Solitary lesions were successfully removed either by enucleation or by distal pancreatectomy in all 19 patients with benign disease. CONCLUSIONS: This high success rate in the management of occult insulinomas suggests that extensive preoperative radiologic investigation is neither indicated nor cost-effective.
Authors: Brian K P Goh; London L P J Ooi; Peng-Chung Cheow; Yu-Meng Tan; Hock-Soo Ong; Yaw-Fui A Chung; Pierce K H Chow; Wai-Keong Wong; Khee-Chee Soo Journal: J Gastrointest Surg Date: 2009-03-17 Impact factor: 3.452