The efficacy of adjuvant chemotherapy for older adults with stage II/III gastric cancer

Background: Adjuvant chemotherapy is recommended as the standard treatment for patients with stage II/III resected gastric cancer. However, it is unclear whether older patients also benefit from an adjuvant chemotherapy strategy. This study aimed to investigate the clinical impact of adjuvant chemotherapy in older patients with stage II/III gastric cancer. Methods: This retrospective, real-world study analyzed 404 patients with stage II/III gastric cancer visited at our institute between January 2009 and December 2019. The clinical characteristics and outcomes of patients aged 70 years or older who received adjuvant chemotherapy were compared with those who did not receive this type of treatment. Propensity score analysis was performed to mitigate selection bias. Results: Of the 404 patients analyzed, 179 were aged 70 years or older. Fewer older patients received adjuvant chemotherapy than did younger patients (60.9% vs. 94.7%, respectively; P < 0.001). Among patients aged 70 years or older, those who received adjuvant chemotherapy had improved disease-free survival (DFS) (5-year DFS rate, 53.1% vs. 30.4%; P < 0.001) and overall survival (OS) (5-year OS rate, 68.7% vs. 52.1%; P = 0.002) compared to those who did not receive adjuvant chemotherapy. A similar survival benefit was observed in the propensity-matched cohort. Multivariate analysis showed that more advanced stage was associated with poorer OS. Receipt of adjuvant chemotherapy was independently associated with a decreased hazard of death (hazard ratio (HR), 0.37; 95% confidence intervals (CI), 0.20–0.68; P = 0.002). Conclusions: Adjuvant chemotherapy may benefit older stage II/III gastric cancer patients aged ≥ 70 years. Further prospective studies are needed to confirm these findings.