Impact of clinical tumor-node-metastasis staging on survival in gastric carcinoma patients receiving surgery

Preoperative clinical staging of gastric cancer is used to determine therapeutic strategies. However, the impact of the clinical stage on survival has not been completely investigated, although the relationship between pathologic staging and survival outcome has been reported. The aim of the present study was to clarify the predictability of patient survival based on clinical staging and to evaluate the usefulness of staging as an indicator for selecting the treatment modality. A total of 3033 patients who underwent surgery for gastric cancer were included. A survival analysis was conducted based on the seventh edition of the tumor-node-metastasis (TNM) clinical staging system of the American Joint Committee on Cancer. The predictive ability of the TNM clinical stage for survival was evaluated by Harrell's C-index, a measure of the separation of survival distributions. The cumulative 5-year survival rates according to the clinical stage were 94.3 % (IA), 84.7 % (IB), 71.7 % (IIA), 56.1 % (IIB), 55.7 % (IIIA), 42.3 % (IIIB), 22.8 % (IIIC), and 9.1 % (IV). Although no significant difference was observed between clinical stages IIB and IIIA (p = 0.865), significant differences existed between all other clinical stages (p < 0.001). Harrell's C-index applied to these results was 0.825 (95 % confidence interval 0.819-0.831). The seventh edition of the TNM clinical staging system has a strong prognostic ability with a satisfactory C-index and should be considered valuable for selecting therapeutic strategies for the treatment of gastric cancer.