Surgical margin status of patients with pancreatic ductal adenocarcinoma undergoing surgery with radical intent: Risk factors for the survival impact of positive margins

Background: For pancreatic ductal adenocarcinoma (PDAC), surgical margin status is an important pathological factor for evaluating surgical adequacy. In this study, we attempted to investigate predictive factors for the survival impact of positive surgical margins. Materials and Methods: From February 2004 to December 2013, 204 patients were diagnosed with PDAC and underwent surgery with radical intent; 189 patients fulfilled our selection criteria and were enrolled for analysis. Results: For the 189 enrolled patients with PDAC, we found male predominance (112/189, 59%) and a median age of 64 years; most patients were diagnosed with stage IIB disease (n=115, 61%). The positive surgical margin rate was 21% (n=40). Carbohydrate antigen 19-9 (CA19-9) level higher than 246 U/ml (odds ratio (OR)=2.318; 95% confidence interval (CI)=1.037-5.181 p=0.040) and lesion location in the uncinate process (OR=2.996; 95% CI=1.232- 7.284 p=0.015) were the only two independent risk factors for positive surgical margins. Positive retroperitoneal soft-tissue margins were the most frequently observed (24/40, 60%). Overall, positive surgical margins had no survival impact in the 189 patients with PDAC who underwent surgery; however, positive surgical margins had an unfavorable survival impact on patients with stage IIA PDAC who underwent surgery. Conclusion: Retroperitoneal soft-tissue was the most common site for positive surgical margins. Additionally, surgical margin positivity was more likely for tumors located in the uncinate process than for other tumors. Positive surgical margins had an unfavorable survival impact on patients with stage IIA PDAC who underwent surgery.