Impact of resection margin status on survival in pancreatic cancer patients after neoadjuvant treatment and pancreatoduodenectomy

Resection margin status has been recognized as an independent prognostic factor on overall survival in pancreatic cancer patients undergoing surgical resection. However, its impact after neoadjuvant treatment remains uncertain. We analyzed 305 patients with resectable or borderline resectable pancreatic cancer treated with neoadjuvant therapy and pancreatoduodenectomy at 3 tertiary referral centers between 2010 and 2017. Positive resection margin was defined as 1 or more cancer cells at any margin. Overall survival was measured from the date of surgery until death or last follow-up. One hundred and seventy-eight patients received neoadjuvant chemotherapy and 127 received neoadjuvant chemoradiotherapy. The median overall survival was 29.8 months. The 1-, 3-, and 5-year overall survival rates were 79.2%, 44.0%, and 23.5%, respectively. Negative margin was achieved in 275 (90.2%) patients. Negative margin resection patients had a significantly longer overall survival than positive resection margin patients (31.3 vs 16.3 months, P < .001). In univariate analyses, overall survival was associated with age, margin status, histologic grade, ypT, number of positive lymph nodes, perineural invasion, treatment effect, postoperative carbohydrate antigen 19-9, and adjuvant therapy. Positive margin resection, poorly differentiated carcinoma, treatment effect score of 3, postoperative carbohydrate antigen 19-9 of 37 U/mL or higher, and lack of adjuvant therapy were predictive of poor overall survival in multivariate Cox regression analysis. Margin status was an independent predictor of overall survival in patients treated with neoadjuvant therapy and pancreatoduodenectomy, supporting the use of a negative margin resection as a surrogate of adequate oncological resection in this setting. Our findings may also have significant implications for patient stratification in future randomized trials.