Benign fibrous pleural tumor with elevation of insulin-like growth factor and hypoglycemia.

We have reported the case of a 69-year-old woman with a hugh benign fibrous tumor of the left pleura and hypoglycemic seizures. Increased preoperative levels of insulin-like growth factor (IGF II) were present; insulin level was low and plasma levels of somatomedin C were normal. After resection of the 2,400 gm tumor, blood sugar level has remained normal, and IGF II has fallen to normal limits. This appears to be the first reported case documenting elevated serum IGF II in association with a benign fibrous pleural tumor.