Tumor size as a recommendable variable for accuracy of the prognostic prediction of gastric cancer: a retrospective analysis of 1,521 patients.

Background: It is still controversial whether tumor size (Ts) should be considered an important indicator for evaluation the prognosis of gastric cancer (GC). The purpose of this study was to elucidate the prognostic prediction superiority of Ts in the large-scale cohort of GC patients.

Methods: Data from 1,521 patients who underwent the curative resection were analyzed for demonstration the prognostic value of Ts. In addition, a tumor size-node-metastasis (TsNM) classification system was proposed to evaluate the comparative superiorities of the prognostic prediction of GC patients.

Results: With the univariate and multivariate analyses, Ts was identified as an independently prognostic predictor of GC patients, as was T stage. Ts was demonstrated to have smaller Akaike information criterion and Bayesian Information Criterion values within the Cox regression analyses than shown by T stage, which represented the optimum prognostic stratification. TsNM classification was also found to be competent for accurately prognostic evaluation of GC patients. The matched case-control logistic regression showed that TsNM classification could provide very powerful discriminations of patients' overall survival, compared with TNM classification. Additionally, Ts stage was found to enhance the survival discriminations in patients with certain clinicopathological characteristics, including male gender, T4a stage, N0 stage, diffuse type of Lauren classification, or age ≤60 years.

Conclusions: Ts should be recommended as an important clinicopathologic variable to enhance the accuracy of the prognostic prediction of GC clinical patients.