Prognostic Factors and the Role of Adjuvant Chemotherapy in Pathological Node-Negative T3 Gastric Cancer

The role of adjuvant chemotherapy in pathological T3N0M0 (pT3N0M0) gastric cancer (GC) remains unclear. The aim of this study was to analyze the prognostic factors of patients with pT3N0M0 GC and to clarify which ones could benefit from adjuvant chemotherapy. A total of 137 patients with pT3N0M0 GC were recruited between 1994 and 2020. Clinicopathological factors and adjuvant chemotherapy regimens were retrospectively collected. Prognostic factors of disease-free survival (DFS) and cancer-specific survival (CSS) were determined using univariate and multivariate analyses. The chemotherapy group was younger (p = 0.012), had had more lymph nodes retrieved (p = 0.042) and had higher percentages of vascular invasion (p = 0.021) or perineural invasion (p = 0.030) than the non-chemotherapy group. There were no significant differences in DFS (p = 0.222) and CSS (p = 0.126) between patients treated with or without adjuvant chemotherapy. Stump cancer, tumor size and perineural invasion were associated with higher rates of recurrence. Tumor size was an independent prognostic factor for DFS (hazard ratio, 4.55; confidence interval, 1.59-12.99; p = 0.005) and CSS (hazard ratio, 3.97; confidence interval, 1.38-11.43; p = 0.011). Tumor size independently influenced survival outcomes in pT3N0M0 patients who underwent radical surgery with and without adjuvant chemotherapy.