摘要Background:Although the prognostic nutritional index(PNI)may predict surgical outcomes in certain cancers,the impact of PNI on surgical prognosis in patients undergoing pylorus-preserving pancreati-coduodenectomy(PPPD)is unclear.This study aimed to investigate the impact of preoperative PNI on mortality rate and cancer recurrence rate in patients who underwent PPPD.Methods:A total of 718 patients who were diagnosed with periampullary or pancreatic cancer and un-derwent PPPD between January 2012 and December 2016 were analyzed.Patients were categorized into two groups using the optimal cut-off value for PNI,determined by calculating the receiver operating characteristic(ROC)curve and the Youden index.We performed propensity score matching(PSM)anal-ysis to compare the mortality rate and cancer recurrence rate between the two groups.In addition,Cox regression analyses were performed to examine the association of PNI with mortality rate and cancer recurrence rate.Results:Using the 1-year mortality as an endpoint,the area under the ROC curve for PNI was 0.620(opti-mal cut-off value:41.7).We observed significant differences in 1-year(P=0.001),5-year(P=0.002),and overall(P=0.001)mortality;1-year(P=0.013),5-year(P=0.032),and overall(P=0.017)cancer re-currence between groups after PSM.High PNI was significantly associated with reduced 1-year[adjusted hazard ratio(HR)=0.44,95％confidence interval(CI):0.26-0.74,P=0.020],5-year(HR=0.66,95％CI:0.52-0.84,P＜0.001),and overall(HR=0.71,95％CI:0.57-0.88,P=0.002)mortality;1-year(HR=0.70,95％CI:0.52-0.93,P=0.016),5-year(HR=0.78,95％CI:0.62-0.97,P=0.027)and overall(HR=0.78,95％CI:0.63-0.97,P=0.024)cancer recurrence.Conclusions:Preoperative PNI may serve as an independent factor for short-and long-term surgical prog-nosis in cancer patients undergoing PPPD.