A Case of Gastrointestinal Stromal Tumor with Recurrent Hypoglycemia

ABSTRACT

Non-islet cell tumor induced hypoglycemia (NICTH) is attributable to overproduction of insulin-like growth factor-II (IGF-II) by solid tumors, and these tumors usually originate from mesenchymal or epithelial cells. Gastrointestinal stromal tumor (GIST) is a rare mesenchymal tumor and most commonly find in the gastrointestinal tract. It is usually expresses the CD117 (stem cell factor receptor, c-kit) detected by immunohistochemistry. Hypoglycemia associated with GIST is very rare and this has not yet been reported in Korea. A 72-year-old man was hospitalized due to frequent episodes of confusion. It was observed that non-hyperinsulinemic hypoglycemia, an elevated serum IGF-II level and a huge liver mass. The histology of liver mass showed c-kit (CD117) positivity, which was consistent with GIST, but it was surgically unresectable. He was treated with imatinib mesylate. Although he recieved palliative treatment, he still experienced intermittent fasting hypoglycemia. After 2 months, the serum IGF-II level was even higher than before. We changed imatinib mesylate to sunitinib malate and performed radiotherapy on the liver mass. Although the change of the liver mass was not significant, he did not suffer from hypoglycemia for three months afterwards.