Prognostic Factors Of Pancreaticoduodenectomy For Pancreatic Head Cancer And The Establishment Of A Nomogram Prediction Model

Objective:Pancreaticoduodenectomy is one of the common surgical procedures for the treatment of pancreatic periampullary cancer,which is considered one of the most complex procedures in abdominal surgery.In this paper,we analyzed and screened the prognostic factors of patients with pancreatic head cancer receiving pancreaticoduodenectomy by reviewing the available information from the Surveillance.Epidemiology,and End Results(SEER)database in the United States,and established a nomogram prediction model for clinical reference.Methods We screened data from the SEER database of patients diagnosed with pancreatic head cancer between 1973 and 2015.Propensity score matching(PSM)was used to control for confounding factors.Kaplan-Meier(log-rank test)curves were used to compare overall survival.Multivariate Cox regression models were employed to identify and screen for risk factors,and a nomogram prediction model was developed.whose predictive accuracy was verified by calibration plots and ROC curves.Results 4099 patients diagnosed with pancreatic head cancer and received pancreaticoduodenectomy from 2010 to 2015 were obtained intact with a median overall survival(OS)of 22 months,and postoperative survival rates of 74.2%,36.5%and 26.2%at 1.3 and 5 years,respectively,and with a median pancreatic cancer specific survival(CSS)of 24.0 months,and postoperative CSS rates of 71.1%、32.6%and 21.9%at 1,3 and 5 years,respectively.Cox proportional risk regression models showed that age,insurance status,gender,histology,degree of differentiation,T stage,N stage.tumor size,extent of regional lymph node dissection,postoperative radiotherapy,and postoperative chemotherapy were independent factors affecting prognosis.To further assess the effect of adjuvant therapy(postoperative radiotherapy and postoperative chemotherapy)on postoperative survival,propensity score matching was used separately to eliminate bias from other unbalanced covariates in the raw data.After eliminating potential confounding factors such as age,insurance status,gender,degree of differentiation,histology,tumor size,T-stage,N-stage,and postoperative chemotherapy on the effect of postoperative radiotherapy,patients receiving postoperative radiotherapy were found to have a better survival prognosis and diseasespecific survival prognosis than patients not receiving radiotherapy,HR=0.809,95%Cl(0.731-0.894),P<0.001 and HR=0.814,95%CI(0.732-0.904),P<0.001;After eliminating potential confounding factors such as age,insurance status,gender,degree of differentiation,histology,tumor size,T-stage,N-stage,and postoperative radiotherapy on the effect of postoperative chemotherapy,patients receiving postoperative chemotherapy were found to have a better survival prognosis and diseasespecific survival prognosis than patients not receiving chemotherapy,HR=0.703,95%CI(0.633～0.780),P<0.001 and HR=0.736,95%CI(0.658～0.822),P<0.001.Finally,the coefficients β of the Cox proportional risk regression model are used to build the nomogram.calibration plots and ROC curves show that the nomogram has good predictive power.Conclusion Age at diagnosis,health insurance status,gender,histological type and degree of differentiation,T-stage,N-stage and tumor size,extent of intraoperative lymph node dissection,postoperative radiotherapy and postoperative chemotherapy are factors that influence pancreaticoduodenectomy for pancreatic head cancer.Postoperative radiotherapy and postoperative chemotherapy can improve patient survival,but preoperative radiotherapy has not been found to have an improved prognosis for postoperative survival.This still needs to be further validated by more high-quality prospective studies in the future.The nomogram prediction model developed in this paper has good prediction accuracy,which can help clinicians to evaluate and predict the survival of pancreatic head cancer patients after pancreaticoduodenectomy and provide better clinical guidance.