ABSTRACT
OBJECTIVE: To present a case of management of refractory hypoglycemia due to malignant insulinoma with use of everolimus, resulting in recurrent insulin-requiring diabetes. METHODS: This report describes a case of a nonresectable malignant insulinoma in a 78-year-old patient with long-standing type 2 diabetes mellitus. Endogenous hyperinsulinism was confirmed by a fasting test, which revealed a glucose level of 35 mg/dL and an insulin value of 23.7 µIU/mL. Endoscopic ultrasonography, magnetic resonance imaging, and computed tomography identified a pancreatic mass, infiltration of the superior mesenteric vein, and metastatic lesions in the liver. RESULTS: After chemoembolization of the metastatic lesions, hypoglycemia recurred, despite combined treatment with somatostatin analogues, dexamethasone, and diazoxide. Everolimus, an orally administered mammalian target of rapamycin, was used at a daily dose of 5 mg. After 6 months, the hypoglycemia was controlled, and the patient presented with a C-peptide level of 0.2 ng/mL and secondary hyperglycemia that necessitated insulin treatment. CONCLUSION: The orally administered drug everolimus controlled hypoglycemia due to a malignant insulinoma in a patient with prior insulin-requiring diabetes. Secondary hyperglycemia was an acceptable drug effect (to the patient and managing physicians), in light of the complex and often poorly tolerated treatments available for this rare condition.
