Insulinoma: diagnostic strategies and surgical treatment. A 22-year experience

The efficacy of preoperative localization methods and the results of the surgical treatment of insulinoma were studied.

Fifty-nine patients referred for surgical treatment were studied and the results of the diagnostic tools for tumor localization were compared with findings at surgical intervention. The influence of the type of surgical procedure in the immediate and late postoperative course was also studied.

Ultrasonography had a sensitivity of 30%, computed tomography 25%, angiography 54%, portal vein sampling 94%, endoscopic ultrasonography 27% and magnetic resonance 17%. Intraoperative palpation localized 98.2% of the tumors and by the addition of intraoperative echography, all lesions were identified. In 55 patients with benign lesions, 22 enucleations, 25 distal pancreatectomies, 7 pancreatectomies plus enucleation and one duodenopancreatectomy were performed. Malignant tumors were treated by pancreatic resection, postoperative hepatic artery embolization and systemic chemotherapy. There was no postoperative mortality. Pancreatic fistula was the most common complication. Three patients who underwent distal pancreatectomy developed late diabetes (9.3%).

Extensive preoperative investigation, mainly with invasive methods, is not indicated and by combining intraoperative palpation and echography most of the cases can be adequately dealt with. Preservation of pancreatic tissue with enucleation and preservation of the spleen are the best choice for treatment of benign insulinomas.