Spleen-preserving total pancreatectomy and islet autotransplantation with complete preservation of the splenic arterial and venous supply does not impact islet yield and function

Background: Standard total pancreatectomy and islet autotransplantation (TPIAT) for chronic pancreatitis includes splenectomy, but TPIAT can be performed without splenectomy by full preservation of the blood supply to the spleen. Methods: We compared the metabolic and clinical outcomes of patients who underwent TPIAT at our center between 2015 and 2021 with or without splenectomy. A total of 89 patients were included in the study, and 17 of them underwent spleen-preserving total pancreatectomy (SPTP). Results: The two study groups had similar demographic and metabolic parameters. Short-term morbidity and long-term outcomes were similar. The operative time was significantly shorter with splenectomy: a median of 9.91 h (interquartile range [IQR] 8.89-10.83) compared to 10.78 h (IQR 10.2-11.6) for SPTP (P = 0.021). There was no difference between the groups in postoperative morbidity. Metabolic outcomes at 1 year were better in the SPTP group compared to the splenectomy group, with a median daily insulin requirement of 7 units (IQR 4-12) vs 15 units (IQR 7-26; P = 0.049) and a median C-peptide at 1 year of 0.65 (IQR 0.40-1.26) vs 1.00 (IQR 0.80-1.90; P = 0.63). The reduction in morphine milligram equivalents per day over time was significantly better in the SPTP group (P < 0.001), as was the decrease in pain score (P < 0.001). Conclusion: TPIAT with full arterial and venous preservation of the spleen had no adverse impact on islet yield or function. TPIAT can be safely and effectively performed with preservation of the spleen and the entire splenic artery and vein. The spleen should be preserved when feasible in every TPIAT surgery.