Pancreatogenic Type 3c Diabetes After Major Pancreatic Resections for Chronic Pancreatitis: A Single-Center Experience of More than 100 Surgical Cases

<b>Background/Objectives:</b> The impact of surgical resection for chronic pancreatitis on subsequent endocrine outcomes remains unclear. <b>Methods:</b> A single-center analysis of patients with chronic pancreatitis who underwent either a parenchymal-preserving surgery (PPS) or a total pancreatectomy (TP) with/without islet autotransplantation (IAT) between 2018 and 2024 was performed. Preoperative and postoperative changes in hemoglobin A1C (HbA1C) and long-acting insulin dose were compared. Univariate and multivariate analysis was performed to identify factors associated with 1-year insulin independence. <b>Results</b>: A total of 104 patients underwent surgery for chronic pancreatitis between 2018 and 2024. A total of 35 (33.7%) patients underwent TPIAT, 8 (7.7%) underwent TP, and 61 (58.7%) underwent PPS (n = 18 Whipple, n = 38 distal pancreatectomy, n = 5 drainage procedure). Median HbA1C increased after surgery (5.7% vs. 6.8%, <i>p</i> < 0.001). The majority of patients (n = 73, 70.2%) were discharged postoperatively without any basal insulin requirement. Of the 31 patients discharged on basal insulin, 18 patients (58.1%) were not on basal insulin preoperatively; the other 13 patients (41.9%) that were on basal insulin preoperatively had a median change in their postoperative basal insulin dose of -5 units [IQR: -12--1]. A total of 46 patients (52.3%) were insulin independent at one year, with PPS more favorable than TPIAT (47.6% vs. 21.7%, <i>p</i> < 0.001) and less likely to have been on preoperative basal insulin. <b>Conclusions:</b> Surgery for chronic pancreatitis resulted in an increase in HbA1C postoperatively; however, diabetes remained well-controlled as the majority of patients remained off basal insulin at one year from surgery. PPS patients were more likely to be insulin-independent.