Development and External Validation of a Simplified Nomogram Predicting Individual Survival After R0 Resection for Gastric Cancer: An International, Multicenter Study

Previous studies have developed three nomograms for the individual prediction of overall survival after gastric cancer surgery. In this study, the performance of these nomograms was evaluated and compared with that of a simplified nomogram in a multinational cohort of patients.

Clinical data from patients who underwent resection (R0) with curative intent for GC at three specialized centers (two from China and one from Italy) and data from the Surveillance, Epidemiology, and End Results database were retrospectively analyzed.

The study analyzed 9810 patients, and the simplified nomogram was developed based on the following factors present in all models: age, sex, depth of invasion, and number of metastatic lymph nodes. In the decision curve analyses, the simplified nomogram demonstrated similar net benefit gains relative to previous models. The discriminative ability of the simplified nomogram was similar to those of the three existing nomograms, and calibration of the simplified nomogram resulted in a predicted survival similar to the actual survival. The predictive ability of the simplified nomogram was superior to that of the American Joint Committee on Cancer (AJCC) stage using Eastern and Western validation data (p < 0.01). Additionally, the simplified nomogram predicted the probabilities within each AJCC stage to illustrate the heterogeneity of risk within each stage.

The novel simplified nomogram simplifies the assessment of individual survival after R0 resection for GC without sacrificing predictive ability. It also has potential for use with other databases and for clinical applications.