Improvement of body weight and nutritional status in gastric cancer patients enhances the efficacy of nivolumab therapy

Background: Nivolumab improves the overall survival (OS) of patients with advanced gastric cancer (AGC) refractory to at least two previous chemotherapy regimens. Here, we investigated whether changes in body weight and nutrition from 1st -line chemotherapy to nivolumab could affect the efficacy of nivolumab. Methods We retrospectively examined patients with AGC treated with nivolumab between July 2016 and August 2020. This study examined the correlation between changes in body weight and nutritional status up to the start of nivolumab treatment, and the overall survival (OS) and progression-free survival (PFS) after the initiation of nivolumab treatment. Nutritional status was examined using the C-reactive protein/albumin ratio (CAR). Results Ninety-eight patients were enrolled. In our study, a loss in body weight (LBW) from the start of the first treatment of < 4.5% led to OS prolongation. The median OS in the LBW < 4.5% group and in the LBW ≥ 4.5% group was 11.4 months (95% confidence interval [CI] 6.6–14.3) and 3.6 (95%CI 2.2–5.1) months, respectively (hazard ratio [HR] 0.42; 95%CI 0.26–0.66; p < 0.001). Similarly, the change in CAR from first-line chemotherapy (ΔCAR) affected OS, and the ΔCAR < 0.01 group had a better prognosis than ΔCAR ≥ 0.01 group. The median OS in the ΔCAR < 0.01 group and in the ΔCAR ≥ 0.01 group was 9.4 (95%CI, 5.1–13.7) and 4.5 (95%CI 4.0–5.0) months, respectively (HR 0.59; 95%CI 0.37–0.93; p = 0.002). Moreover, the median OS in the group with both LBW < 4.5% and ΔCAR < 0.01 was 12.9 months (95%CI 6.8–19.0). Furthermore, the LBW < 4.5% group showed statistically significantly better PFS (median PFS 2.7 vs. 2.0 months; HR 0.63, 95%CI 0.42–0.94; p = 0.021). Conclusion Our study suggested that LBW and deterioration of nutritional status from the start of first-line chemotherapy are poor prognostic factors in AGC patients who received nivolumab as third- or later-line therapy. Early intervention to maintain body weight and nutritional status from the initiation of prior chemotherapy may improve the efficacy of immune checkpoint inhibitors.