Score for the Overall Survival Probability of Patients With Pancreatic Adenocarcinoma of the Body and Tail After Surgery: A Novel Nomogram-Based Risk Assessment

Pancreatic adenocarcinoma of the body and tail often has dismal prognosis and lacks a specific prognostic stage. The aim of this study was to construct a nomogram for predicting survival of patients with pancreatic adenocarcinoma of the body and tail after surgery. Data of patients were selected from the Surveillance, Epidemiology, and End Results (SEER) database and medical records of Sun Yat-sen University Cancer Center (SYSUCC). In multivariate analysis for overall survival (OS) analysis, the following 6 variables were identified as independent predictors and incorporated into the nomogram: age, tumor differentiation, tumor size, lymph node ratio (LNR) and chemotherapy. A nomogram was built based on independent risk predictors. The concordance index (C-index) for nomogram, Tumor-Node-Metastasis (TNM) 7th and 8th stage system were 0.775 (95% confidence interval (CI), 0.731-0.819), 0.617 (95%CI, 0.575-0.659) and 0.632 (95%CI, 0.588-0.676), respectively. The calibrated nomogram predicted survival rates which were closely corresponded to the actual survival rates. Furthermore, the values of area under receiver operating characteristic (ROC) curves (AUC) of nomoram were higher than those of TNM 7th or 8th stage system in predicting 1-, 2- and 3-year survival of patients in training and external validation cohorts. The well-calibrated nomogram could be used to predict prognosis for patients with pancreatic adenocarcinoma of the body and tail after surgery.