Impact of Resection Margin Status in Patients with Pancreatic Cancer: a National Cohort Study

Aim: To assess the predictors and influence of resection margins and the role of neoadjuvant and adjuvant therapy on survival for a national cohort of patients with resected pancreatic cancer.

Methods: Using the National Cancer Data Base between 2004 and 2016, 56,532 patients were identified who underwent surgical resection for pancreatic adenocarcinoma. Univariate and multivariate models were employed to identify factors predicting R0/R1 resection and assess the impact on survival.

Results: In total, 48,367 (85.6%) patients were found to have negative margins (R0) compared to 8165 (14.4%) who had microscopic residual tumor (R1). Factors predicting positive margin on univariate analysis included male gender, Medicare, advanced stage, moderately or poorly differentiated tumor, lymphovascular invasion, and tumors > 2 cm. Factors predicting R0 resection included receipt of neoadjuvant therapy and treatment at an Academic/Research Center. Following adjustment for other factors, margin status remained an independent predictor for overall survival (HR: 1.24; 95% CI 1.22-1.27, p < 0.001) (1-, 3-, and 5-year overall survival rates (R0: 77%, 37%, and 25% vs R1: 62%, 19%, and 10%).

Conclusions: A positive margin predicts a poorer survival than R0 resections regardless of stage and receipt of adjuvant therapy. Several modifiable factors significantly predict the likelihood of R0 resection including neoadjuvant treatment and treatment at Academic/Research Programs. Knowledge about these factors can help guide patient management by offering neoadjuvant treatment modalities at Academic as well as Community hospitals.