Abstract
We experienced a case of low-grade malignant insulinoma which was diagnosed by examining blood samples from the hepatic vein after selective intra-arterial calcium injections (SICI). A 77-year-old man who had had a history of epilepsy was treated by antiepileptic drugs for over 10 years. He was admitted to our hospital in an emergency because of unconsciousness. The blood glucose level was extremely low (29 mg/dl) and then the abdominal contrast-enhanced computed tomography showed a mass with a diameter of 1 cm in the body of the pancreas. Endoscopic retrograde cholangiography showed partial stenosis of the pancreatic ductin the body, which seemed to be caused by the extensive mass and dilatation of the pancreatic duct in the tail. However, the massive lesion was not detected by angiography. The serum insulin level in the hepatic vein by SICI into the distal splenic artery was over two times the control level. Therefore, this mass could be diagnosed as insulinoma in the tail of the pancreas. The body and tail of the pancreas were resected along with simultaneous splenectomy. The pathological diagnosis was made as islet cell carcinoma of low-grade malignancy and medullary type.
