Abstract: Objective   To analyze the risk factors for the prognosis of Periampullary carcinoma and establish a prognostic model. Methods   Clinical data of periampulla carcinoma patients from SEER database were retrospectively analyzed.According to the set criteria,1775 patients were included and divided into the modeling group(1 242 case) and the validation group(533 case) in a 7∶3 ratio.In the modeling group,Cox proportional risk regression model was used to screen the risk factors influencing the survival and prognosis of periampullary carcinoma,and a Nomogram was constructed based on the regression analysis results.The predictied efficiency of the model was verified in the modeling group and the verification group respectively. Results   Age,T stage,N stage,degree of tumor differentiation,pathological type and operation were found to be risk factors for periampullary carcinoma by Cox regression model.The above six variables were included in the prediction model and a Nomogram was drawn to predict 1year,3year and 5year survival rates.C index in modeling group and verification group was 0.7047(95%CI：0.6854,0.7241) and 0.7001(95%CI：0.6689,0.7314),respectively.The AUC values of 1year,3year and 5year ROC curves in the modeling group were 0.766、0.756 and 0.757,respectively,and those of 1year,3year and 5year ROC curves in the verification group were 0.736、0.733 and 0.742,respectively.The correction curve showed that the predictors of survival rate was consistent with the actual survival rate,and the decision curve showed that the prediction model had certain clinical value.Conclusion   The prognostic model of periampullary carcinoma has good predictive value.

Key words: periampullary carcinoma, prediction model, C24.1