A Malignant Insulinoma Transformed into a Glucagonoma Syndrome

Publisher Website
Google Scholar
Abstract
A 55-yr-old man was admitted to the Hospital of Tohoku University in 1970, when physical examination and laboratory findings revealed malignant insulinoma with metastases to the liver. Streptozotocin treatment, totaling 79.5 g for 1 yr, improved his clinical symptoms. After discharge he was well until 1977, when he complained of palpitation and dyspnea, and he was hospitalized in September 1977 because of anorexia and a loss of body weight. Laboratory findings revealed anemia, with a decrease both in serum albumin and iron. His fasting blood glucose was 74 mg/dl and plasma insulin (IRI) 25 μU/ml. His plasma IRI increased slightly after the stimuli of glucose, arginine, and glucagon. In contrast, his plasma glucagon (IRG) increased at fasting (3372 pg/ml) and became markedly elevated after arginine or glucose was administered. After his final admission, diazoxide improved his symptoms temporarily; streptozotocin could not be administered because of dyspnea and palpitation. On 24 January 1978, he fell suddenly into a coma and 2 days later he died. An autopsy revealed a large pancreatic tumor and metastases to the liver. Measurement of hormones from the tissues revealed a smaller amount of IRI in the pancreatic tumor and liver metastases compared with that in the uninvolved pancreas. In contrast, IRG contents had increased in the pancreatic tumor and hepatic metastases. In addition to the insulin cells, numerous cells with glucagon and somatostatin were observed in morphologic examinations. This indicated a mixed endocrine pancreatic tumor exhibiting typical symptoms of insulinoma initially and a glucagonoma syndrome later.