Construction and validation of a predictive model for the prognosis of papillary renal cell carcinoma： a retrospective study based on the Surveillance，Epidemiology，and End Results database

Abstract:

Objective To establish a nomogram model for evaluating the prognosis of papillary renal cell carcinoma（PRCC）.Methods Clinical data were collected from 6 028 patients with PRCC in the Surveillance，Epidemiology，and End Results（SEER） database，and they were randomly divided into the training cohort with 4 220 patients and the validation cohort with 1 808 patients. A Cox proportional-hazards regression model analysis was used to identify the clinicopathological features associated with the prognosis of PRCC. A nomogram was established based on the Cox model to predict the prognosis of patients with PRCC； the receiver operating characteristic（ROC） curve and C-index were used to evaluate the discriminatory ability of the model，and the calibration curve was used to assess the predictive accuracy of the nomogram model.Results The data of 6 028 patients with PRCC were retrieved from the SEER database. The Cox proportional-hazards regression model analysis showed that age at diagnosis，grade，tumor-node-metastasis stage（TNM，AJCC，7th edition），surgical treatment，tumor number，and marital status were significant independent prognostic variables，and all the variables were combined to establish a nomogram. The nomogram model had a C-index of 0.807（95%CI=0.779-0.834） in the training cohort and 0.800（95%CI=0.759-0.841） in the validation cohort，and AJCC TNM stage had a C-index of 0.686（95%CI=0.667-0.706） in the training cohort and 0.668（95%CI=0.638-0.697） in the validation cohort，suggesting that compared with AJCC TNM stage，the nomogram model exhibited a good predictive ability for overall survival（OS） rate in the training and validation cohorts. The calibration curve showed high consistency between the OS rate predicted by the nomogram and the actual OS rate.Conclusion The nomogram established in this study shows an excellent predictive performance and can help to evaluate the OS of patients with PRCC，thereby providing a basis for developing individualized treatment strategies.