Metabolic studies and glucagon gel filtration pattern before and after surgery in a case of glucagonoma syndrome.

A case of glucagonoma syndrome with necrolytic migratory erythema, glossitis, anemia, hyperglucagonemia and a malignant, pancreatic A-cell tumour in a 68-year-old male is described. Gel filtration of the highly elevated circulating glucagon immunoreactivity (2200 pg/ml) demonstrated 60% pancreatic glucagon and 30% "proglucagon". Metabolic studies before operation demonstrated suppression of the total plasma glucagon concentration on oral glucose tolerance test, unchanged total plasma glucagon concentration during intravenous glucose tolerance test and insulin-induced hypoglycemia. Administration of arginine was followed by a rise in both the pancreatic glucagon and the "proglucagon", whereas alanine increased only the pancreatic glucagon. The plasma somatostatin level was immeasurable preoperatively. Somatostatin infusion completely suppressed the release of the pancreatic glucagon but did not significantly affect the "proglucagon". After removal of the tumour the skin lesions disappeared and the total plasma glucagon values fell to normal levels (120 pg/ml). Also, other abnormal laboratory findings returned to normal, including the preoperatively observed renal glucosuria.