Outcome after total pancreatectomy with islet autotransplantation: A European single-center study

Background and aims: Chronic pancreatitis may cause intractable abdominal pain, with total pancreatectomy sometimes being the last resort. To mitigate the subsequent diabetes, total pancreatectomy can be followed by islet autotransplantation (TP-IAT). The primary aim of this study was to assess the outcomes in patients undergoing TP-IAT at Karolinska University Hospital with respect to safety, postoperative complications, and islet graft function. A secondary aim was to compare liver to skeletal muscle as autotransplantation sites. Methods: Single-center observational cohort study on patients undergoing TP-IAT. Islets were transplanted either into the liver or skeletal muscle. Data on baseline characteristics and pretransplantory conditions were collected. Outcome measures included mortality and major postoperative complications as well as the glycemic measures: insulin use, fasting C-peptide, and HbA1c. Results: Between 2004 and 2020, 24 patients underwent TP-IAT. Islets were transplanted into the liver in 9 patients and into skeletal muscle in 15 patients. There was no 90-day mortality, and major complications (Clavien-Dindo > IIIa) occurred in 26.7%, all related to the procedure of total pancreatectomy. Fasting C-peptide could be detected postoperatively, with higher levels in patients receiving islet autotransplantation into the liver (p = 0.006). Insulin independence was not achieved, although insulin doses at last follow-up were significantly lower in patients receiving islet autotransplantation into the liver compared to skeletal muscle (p = 0.036). Conclusion: TP-IAT is safe and associated with tolerable risk, the component of islet autotransplantation being seemingly harmless. Although islet grafts maintain some endocrine function, insulin independence should not be expected. Regarding islet autotransplantation sites, the liver seems superior to skeletal muscle.