BACKGROUND
Previously, in patients suffering from insulin deficient DM after a partial or total pancreatectomy as treatment for a benign pancreatic tumor, insulin treatment has only led to severe fluctuation in the blood glucose level, and frequently to sudden hypoglycemia due to glucagon deficiency and lack of delicate insulin control. Several worldwide reports have suggested that autologous transplantation of islet cells isolated from an unaffected portion of a resected pancreas, mostly for the cure of chronic pancreatitis or a pancreatic tumor without immunosuppressive agent treatment, resulted in good glycemic control, and even in the prevention of DM. Attempts were made to evaluate the effect of islet autotrans-plantation for glycemic control in eight patients undergoing a pancreatectomy for a benign pancreatic tumor. METHOD: Between December 2001 and October 2003, an islet autotransplantation was performed in eight patients patholologically confirmed with benign pancreatic tumors following a pancreatectomy. There was no past medical history of DM in any of the patients, but impaired glucose tolerance(IGT) was detected in 2 patients on a 75g oral glucose tolerance test(oral GTT), and was also suspected in a pre-pancreatectomy state patient. Islets were isolated by ductal perfusion, using the cold collagenase P and semi-automated method, and purified on a density gradients using a COBE 2991 cell processor or tube system of Ficoll solution. After being confirmed as a benign pancreatic tumor, the cultured islet cells were transplanted to the liver through the portal vein. Each patient was transplanted with a mean islet mass of 3,190+/-896 islet equivalents per kilogram of body weight. The median follow-up period was 12 months, with the longest being 36 months. All patients underwent follow-up for oral GTT, HbA1c and complication of DM, pancreatectomy, or transplantation within this period. RESULTS: On the 75g oral GTT, a normal glucose tolerance(NGT) was maintained until the last follow-up month in five of the eight patients undergoing islet autotransplantation. DM recurred in three of the eight patients undergoing islet autotransplantation, with to cases in a state of IGT and 1 case of NGT at the initial stage. The HbA1c levels were not significantly changed between pre-pancreatectomy and post-islet transplantation period. The amplitude of the decrease in the postprandial 2 hour glucose level was larger than that of the fasting glucose level between the pre- and post-transplantation periods, but this was not statistically. Also, the elevation of the postprandial C-peptide level was larger than the fasting C-peptide during the post-transplantation period, but again, this was not significant. No complications occurred in relation with the islet transplantation, portography, DM and hypoglycemia. CONCLUSION: Islet transplantation could prevent and reverse the diabetic process in patients undergoing a pancreatectomy for a benign pancreatic tumor, with some exception such as those with a small transplanted islet mass or with initial insulin resistance. The 2 hour postprandial changes in the glucose and C- peptide levels on the oral GTT somewhat reflected insulin secretory function of the remaining and newly transplanted islet cells. Pancreatic islet autotransplantation is the most prospective method for the prevention or cure of insulin deficient DM following a pancreatectomy for a benign pancreatic tumor.