Solitary fibrous tumor associated with non-islet cell tumor hypoglycemia.

A 79-year-old man presented with abnormal fluttering movements of his extremities early in the morning. Fasting hypoglycemia was believed to be the cause of the movements. A computed tomographic scan showed a large mass in the left inferior hemithorax. Non-islet cell tumor hypoglycemia was suspected, and the mass was resected while the patient was under glucose supplementation therapy. The plasma glucose level became stable shortly after tumor excision. The resected tumor was diagnosed as a solitary fibrous tumor producing insulin-like growth factor II. In the follow-up examination approximately 2 years after the surgery, no recurrence of the tumor was observed, and the plasma glucose level was stable.