Survival Analysis of Stage II Gastric Cancer Patients after D2 Gastrectomy: A Chinese People-based Research Running Head: Survival of Stage II Gastric Cancer

Objective: The benefit of adjuvant chemotherapy is still controversial for stage II gastric cancer patients. This study aims to identify prognostic factors to guide individualized treatment for stage II gastric cancer patients.Methods: We retrospectively reviewed 1121 stage II gastric cancer patients who underwent D2 radical gastrectomy from 2007-2017 in the Sixth Affiliated Hospital of Sun Yat-sen University, FuJian Medical School Affiliated Union Hospital and Sun Yat-sen University Cancer Center. Propensity score matching (PSM) was used to ensure that the baseline data were balanced between the adjuvant chemotherapy (AC) group and surgery-only group. Kaplan-Meier survival and multivariate Cox regression analyses were carried out to identify independent prognostic factors. Results: In univariate analysis, after propensity score matching, age, tumor location, tumor size, CEA, T stage and N stage were associated with overall survival (OS). Multivariate analysis illustrated that age ≥60 years old, linitis plastica and T4 were independent risk factors for OS, but lower location and adjuvant chemotherapy were protective factors. Conclusion: Adjuvant chemotherapy is helpful for stage II gastric cancer patients. These prognostic factors can help guide individual therapy.