Insulinoma

Abstract

Insulinoma is the most common pancreatic islet cell tumor, usually presenting with symptoms of neuroglycopenia. Diagnosis depends on a high index of suspicion, together with the demonstration of endogenous hyperinsulinemic hypoglycemia. Although the requirement for preoperative localization is controversial, the minimally invasive but highly sensitive endoscopic ultrasonography allows for a more focused surgery, shorter exploration time, and the option of laparoscopic surgery. Intra-arterial calcium stimulation test can be considered in persistent or possibly multifocal disease. Intraoperative ultrasonography is also recommended to assist tumor localization and minimize complications. The use of a biostator or rapid insulin assays intraoperatively may be helpful if multiple lesions are present. The surgical cure rate for benign insulinomas approaches 100%. For those with residual or metastatic disease, symptomatic control can be achieved with diazoxide or somatostatin analogues. Multimodality therapy is usually required for metastatic disease: with control of hypoglycemia, prolonged symptom-free survival can be expected.