Evaluation of Insulin Independence Using C-Methionine Positron Emission Tomography After Living-donor and Brain-dead Donor Pancreas Transplantation

We recently reported that ¹¹C-methionine positron-emission tomography (PET) is clinically useful for the evaluation of the pancreatic function of the living donor. The objective of this study was to evaluate the postoperative insulin independence in 10 living donor (LD) and 10 brain-dead donor (BD) pancreas transplantations for 20 patients with type I diabetes mellitus by using ¹¹C-methionine PET. After 6 months, PET/computed tomography was performed 30 minutes after ¹¹C-methionine (370–740 MBq) injection. The uptake in the pancreas was expressed as the standardized uptake value (SUV). Patient survival rates were 100% at 5 years for LD transplantations and at 2 years for BD transplantations. Insulin independence was 60% for LD transplantations at 5 years and 75% for BD transplantations at 2 years. There were no major surgical complications such as vascular thrombosis, intra-abdominal abscess, and graft pancreatitis. The SUVs for LD and BD pancreas transplantations with insulin independence were 7.2 ± 1.8 and 10.4 ± 2.3, respectively. The SUVs for LD pancreas transplantations with insulin dependence and BD pancreas transplantations with graft failure were 3.6 ± 1.1 and 2.9 ± 1.0, respectively. At 5 years after transplantation, for the LD transplants, the insulin-independent rate was 100% for the graft recipients with an SUV higher than 5, and the median insulin independence duration of the graft recipients with an SUV less than 5 was 7 months (P < .01). The ¹¹C-methionine PET may be a potent modality to predict long-term insulin independence and the avoidance of pancreas graft failure.