Neoadjuvant therapy affects margins and margins affect all: perioperative and survival outcomes in resected pancreatic adenocarcinoma.

BACKGROUND: Resection margin status is an important prognostic factor in pancreatic cancer; however, the impact of positive resection margins in those who received neoadjuvant therapy remains unclear. The current study investigates the prognostic impact of resection margin status after neoadjuvant therapy and pancreaticoduodenectomy for patients with pancreatic adenocarcinoma. METHODS: Patients who underwent pancreaticoduodenectomy for pancreatic adenocarcinoma between 2006 and 2013 were identified from the National Cancer Database. Multivariable logistic regression analysis was utilized to examine the predictive value of neoadjuvant therapy for resection margin status. Long-term outcomes were compared using a Cox proportional hazards model. RESULTS: 7917 patients were identified in total: 1077 (13.6%) and 6840 (86.4%) patients received neoadjuvant therapy and upfront surgery, respectively. Upfront surgery was independently predictive of a positive margin (25.7% vs. 17.7%; OR, 1.54) compared to neoadjuvant therapy. After receipt of neoadjuvant therapy, positive margins (median overall survival, 18.5 vs. 25.9 months; HR, 1.58) remained significantly associated with poor survival on multivariable analysis. DISCUSSION: While neoadjuvant therapy is associated with decreased R1/R2-resection rates after pancreaticoduodenectomy, the poor prognostic impact of positive margins is not abrogated by neoadjuvant therapy, stressing the need for complete tumor clearance and postoperative treatment even after neoadjuvant therapy.