Margin-Positive Pancreatic Ductal Adenocarcinoma during Pancreaticoduodenectomy: Additional Resection Does Not Improve Survival.

BACKGROUND: The impact of resecting positive margins during pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDA) remains debated. Additionally, the survival benefit of resecting multiple positive margins is unknown.
METHODS: We identified patients with PDA who underwent PD from 2006 to 2015. Pancreatic neck, bile duct, and uncinate frozen section margins were assessed before and after resection of positive margins. Survival curves were compared with log-rank tests. Multivariable Cox regression assessed the effect of margin status on overall survival.
RESULTS: Of 501 patients identified, 17.3%, 5.3%, and 19.7% had an initially positive uncinate, bile duct, or neck margin, respectively. Among initially positive bile duct and neck margins, 77.8% and 67.0% were resected, respectively. Although median survival was decreased among patients with any positive margins (15.6 vs. 20.9 months; p = 0.006), it was similar among patients with positive bile duct or neck margins with or without R1 to R0 resection (17.0 vs. 15.6 months; p = 0.20). Median survival with and without positive uncinate margins was 13.8 vs. 19.7 months (p = 0.04). Uncinate margins were never resected. Resection of additional margins when the uncinate was concurrently positive was not associated with improved survival (p = 0.37). Patients with positive margins who received adjuvant therapy had improved survival, regardless of margin resection (p = 0.03). Adjuvant therapy was independently protective against death (hazard ratio 0.6, 95% CI 0.5-0.7).
CONCLUSIONS: Positive PD margins at any position are associated with reduced overall survival; however, resection of additional margins may not improve survival, particularly with concurrently positive uncinate margins. Adjuvant chemotherapy improves survival with positive margins, regardless of resection.