Nomogram Based on Body Composition and Prognostic Nutritional Index Predicts Survival After Curative Resection of Gastric Cancer

Rationale and Objectives: This study aimed to identify independent prognostic factors for gastric cancer (GC) patients after curative resection using quantitative computed tomography (QCT) combined with prognostic nutritional index (PNI), and to develop a nomogram prediction model for individualized prognosis. Materials and Methods: This study retrospectively analyzed 119 patients with GC who underwent curative resection from January 2016 to March 2018. The patients' preoperative clinical pathological data were recorded, and all patients underwent QCT scans before and after curative resection to obtain QCT parameters: bone mineral density (BMD), skeletal muscle area (SMA), visceral fat area (VFA), subcutaneous fat area (SFA) and CT fat fraction (CTFF), then relative rate of change in each parameter (A BMD, A SMA, A VFA, A SFA, A CTFF) was calculated after time normalization. Multivariate Cox proportional hazards was used to establish a nomogram model that based on independent prognostic factors. The concordance index (C-index), area under the time-dependent receiver operating characteristic (ROC) curve and clinical decision curve were used to evaluate the predictive performance and clinical benefit of the nomogram model. Results: This study found that Delta CTFF, Delta VFA, Delta BMD and PNI are independent prognostic factors for overall survival (OS) (hazard ratio: 1.034, 0.895, 0.976, 2.951, respectively, all p < 0.05). The established nomogram model could predict the area under the ROC curve of OS at 1, 3 and 5 years as 0.816, 0.815 and 0.881, respectively. The C-index was 0.743 (95% CI, 0.684-0.801), and the decision curve analysis showed that this model has good clinical net benefit. Conclusion: The nomogram model based on body composition and PNI is reliable in predicting the individualized survival of underwent curative resection for GC patients.