Diagnosis and management of insulinoma

Surgery for insulinoma represents one of the best examples of the application of the principles of physiology and pathology in therapeutics. Seven new cases of insulinoma are presented. New diagnostic tests including radioimmunoassay double antibody insulin levels and a diagnostic trial of diazoxide, an anti-insulin agent, were used. Six lesions were benign; four were treated by enucleation and two by distal pancreatectomy. The remaining patient had palliative cholecystojejunostomy for malignant insulinoma followed by chemotherapy with streptozotocin. Selective celiac angiography can now demonstrate the majority of insulinomas. With refinements in technic more nonpalpable lesions will be demonstrated, thus simplifiying the operative approach. Since 1958, 527 cases have been reported in the literature. Tabulation of nonpalpable lesions reveals that 53 per cent were located in the head of the pancreas, the remainder in the body and tail. These figures suggest that if no lesion can be located by arteriography or palpation, blind distal pancreatectomy should be performed. At this point, if no hyperglycemic response is obtained and serial frozen sections give negative results, subtotal pancreatectomy (95 per cent) will remove 90 per cent of these occult tumors.