Multicenter Study on the Safety and Efficacy of First-Line Nivolumab-Combination Chemotherapy in Patients Aged 75 Years and Older with Unresectable Advanced or Recurrent Gastric Cancer.

[INTRODUCTION] Nivolumab combined with chemotherapy has been approved as the first-line treatment for HER2-negative, unresectable, advanced, or recurrent gastric cancer. Patients aged ≥75 years have impaired organ function and comorbidities that increase the risk of adverse events, including immune-related adverse events more often than younger patients, potentially limiting the continuation of treatment. In this multicenter study, we aimed to evaluate the safety and efficacy of first-line nivolumab chemotherapy in older patients.

[METHODS] We retrospectively analyzed data from 103 patients treated with first-line nivolumab combination chemotherapy for unresectable, advanced, or recurrent gastric cancer at 12 institutions between November 2021 and January 2023. The participants were divided into groups A (<75 years, n = 67) and B (≥75 years, n = 36).

[RESULTS] The mean age was 63.9 years in Group A and 78.6 years in Group B. Body weight was significantly lower (p = 0.041), and performance status 0-1 and hypertension were more prevalent in Group B (both p < 0.01). Chemotherapy regimens and incidence of grade ≥3 immune-related adverse events were similar between the groups. The median overall survival was 15.2 months in Group A and was not reached in Group B; this difference was not significant (p = 0.689).

[CONCLUSIONS] First-line chemotherapy with nivolumab is safe and effective in patients aged ≥75 years with a good performance status, as in younger patients, suggesting that it is a valid treatment option for the former subgroup.