Diabetes mellitus is associated with unfavorable pathologic features, increased postoperative mortality, and worse long-term survival in resected pancreatic cancer

Background: The risk of pancreatic ductal adenocarcinoma (PDAC) is increased in patients with diabetes mellitus (DM), particularly in those with new-onset DM. However, the impact of DM on outcomes following pancreatic surgery is not fully understood. We sought to explore the effects of DM on post-resection outcomes in patients undergoing either upfront resection or following neoadjuvant treatment (NAT). Methods: Resections for PDAC between 2007 and 2016 were identified from a prospectively-maintained database. Data on demographics, pathology, and perioperative outcomes were compared between patients with or without DM. Survival analysis was performed using Kaplan-Meier curves and adjusted for confounders by a Cox-proportional hazards model. Results: 662 patients were identified, of whom 277 (41.8%) had DM. Diabetics were more likely to be male, had higher BMI, and higher ASA-scores. At pathology, DM was associated with larger tumors (30 vs. 26 mm; p = 0.041), higher rates of lymph-node involvement (69% vs. 59%; p = 0.031) and perineural invasion (88% vs. 82%; p = 0.026). Despite having similar rates of complications, diabetics experienced higher 30-day mortality (3.2% vs. 0.8%; p = 0.019). Median overall survival was worse in diabetic patients (18 vs. 34 months; p < 0.001); this effect was more pronounced in patients with NAT (18 vs. 54 months; p < 0.001). At multivariate analysis, DM was confirmed as an independent predictor of post-resection survival. Conclusion: DM is a common comorbidity in PDAC and is associated with unfavorable pathology, as well as worse postoperative and oncologic outcomes. The blunted effect on survival is more pronounced in patients who undergo resection following NAT. © 2019