Functional Advantage of Central Pancreatectomy Over Distal Pancreatectomy for Benign or Low‐Grade Malignant Tumors: A Comparative Analysis Based on 75‐g Oral Glucose Tolerance Test

Background Central pancreatectomy (CP) is a function‐preserving procedure for benign or low‐grade malignant lesions in the pancreatic neck or proximal body. However, endocrine function after CP has not been objectively evaluated. Methods We retrospectively analyzed 123 patients who underwent CP ( n = 38) or distal pancreatectomy (DP; n = 85) for benign or low‐grade malignant tumors. Short‐ and long‐term outcomes were compared between groups. Among 37 patients (CP; n = 12, DP; n = 25) underwent a 75‐g oral glucose tolerance test (OGTT) before and 1 month after surgery to evaluate endocrine function. Results CP was associated with a higher incidence of postoperative pancreatic fistula than DP (40% vs. 8%; p < 0.001). All CP patients achieved R0 resection with no perioperative mortality or tumor recurrence. The incidence of new‐onset diabetes mellitus was significantly lower after CP than after DP (14.8% vs. 50.9%, p = 0.002). In the DP group, the area under the curve (AUC) for blood glucose (BG) increased postoperatively ( p < 0.001), whereas AUCs for immunoreactive insulin (IRI) and C‐peptide immunoreactivity (CPR) decreased ( p = 0.010 and p = 0.022, respectively). Conversely, the CP group showed preserved endocrine function, with no significant postoperative changes in AUCs for BG ( p = 0.351), IRI ( p = 0.723), or CPR ( p = 0.900). Conclusion Compared with DP, which has acceptable short‐term outcomes, CP preserves pancreatic endocrine function. In patients with benign or low‐grade malignant pancreatic tumors with expected long‐term survival, CP should be considered over DP to preserve function.