Adjuvant Therapy Improves Survival in T1N1M0 Gastric Cancer Patients with Poorly Differentiated and Undifferentiated Types

Abstract

Background Whether adjuvant therapy has a survival benefit for all patients with T1N1M0 (Stage IB) gastric cancer (GC) remains controversial. This study attempted to confirm the value of adjuvant therapy in T1N1M0 GC patients with poorly differentiated and undifferentiated type. Methods Overall, 461 T1N1M0 GC patients with poorly differentiated and undifferentiated type following gastrectomy from 2004 to 2018 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score-matched (PSM) analysis was used to reduce bias. Overall survival was analyzed by Kaplan-Meier method and the log-rank test. Cox regression analyses were used to confirm the independent prognostic factors. Results Our study analyzed data from 461 patients in the Seer database who underwent postoperative treatment. Among them, 297 patients received adjuvant therapy. After PSM multivariate regression reveal that adjuvant therapy is associate with OS of the cohort (adjusted HR0.55; 95% CI: 0.38 ~ 0.77). The survival analysis presents that the 5-year OS was significantly higher in patients receiving chemotherapy (69.2% vs.51.5%, p < 0.001) and the 5-year CSS was higher in patients receiving chemotherapy (77.0% vs 61.1% p < 0.001). Conclusion In the population of patients with poorly differentiated and undifferentiated T1N1M0 gastric cancer, postoperative adjuvant therapy has shown potential survival benefits. However, further validation through randomized controlled trials (RCTs) is required to confirm this conclusion.