gastrointestinal disorders
Insulinoma
Treatment of Insulinoma
Surgical resection Diazoxideor sometimesoctreotidefor hypoglycemia Chemotherapy Overall surgical cure rates are about 90%. A small, single insulinoma at or near the surface of the pancreas can usually be enucleated surgically. If a single large or deep adenoma is within the pancreatic body or tail, if there are multiple lesions of the body or tail (or both), or if no insulinoma is found (an unusual circumstance), a distal, subtotal pancreatectomy is done. In<1% of cases, the insulinoma is ectopically located in peripancreatic sites of the duodenal wall or periduodenal area and can be found only by diligent search during surgery. Pancreatoduodenectomy (Whipple procedure) is done for resectable malignant insulinomas of the proximal pancreas. Total pancreatectomy is done if a previous subtotal pancreatectomy proves inadequate. If hypoglycemia continues,diazoxidewith a natriuretic can be used. A somatostatin analog,octreotide, is variably effective and should be considered for patients with continuing hypoglycemia refractory todiazoxide. Patients who respond may be converted to a long-actingoctreotideformulation. Patients usingoctreotidemay also need to take supplemental pancreatic enzymes becauseoctreotidesuppresses pancreatic enzyme secretion. Other medications that have modest and variable effect oninsulinsecretion includeverapamil,diltiazem, andphenytoin. If symptoms are not controlled, chemotherapy may be tried, but response is limited. Streptozotocin has a 30 to 40% response rate and, when combined with 5-fluorouracil, a 60% response rate lasting up to 2 years. Other agents includedoxorubicin, chlorozotocin, and interferon. Newer chemotherapies under investigation for insulinoma includetemozolomide-based regimens,everolimus, orsunitinib. 