Predictive factors of actual 5-y recurrence-free survival after upfront surgery for resectable pancreatic cancer: Exploration of patients who did not require neoadjuvant treatment.

The present study investigated the prognostic factors associated with actual 5-y recurrence-free survival (RFS) after upfront surgery for resectable pancreatic cancer (R-PC) in patients who were deemed not to require neoadjuvant treatment. Between 2007 and 2016, 316 patients who underwent pancreatectomy for radiologically R-PC were retrospectively reviewed to evaluate the predictors of actual 5-y RFS. Predictors were identified using logistic regression analysis of preoperative evaluable factors. The cutoff values for continuous variables were determined based on a minimum p-value approach (model 1) or the value that maximized the rate of 5-y RFS survivors (model 2). Fifty-one patients (16.1%) achieved a 5-y RFS. A tumor size ≤23 mm, the absence of serosal invasion on computed tomography (CT), and Neutrophil-to-Lymphocyte Ratio <1.0, were significantly associated with the 5-y RFS in model 1. A Prognostic Nutritional Index ≥58 and the absence of serosal invasion and extrapancreatic nerve plexus invasion on CT were significantly associated with 5-y RFS in model 2. Only six (11.8%, model 1) and four (7.8%, model 2) patients had all three prognostic factors, and their 5-y RFS rates were 83.3% and 100%, respectively. A modest number of patients who underwent upfront surgery achieved 5-y RFS, but only ~10% of them could be identified preoperatively. Based on these results, almost all R-PC patients are forced to undergo neoadjuvant treatment in daily practice.