347 Background: Nivolumab was established as one of the standard treatments for previously treated advanced gastric cancer (AGC). The aim of this study is to evaluate the frequency of immune-related adverse events (irAEs) with Nivolumab and its impact on treatment efficacy in clinical practice. Methods: We performed multicenter retrospective analysis, which included 90 patients with advanced gastric cancer who received Nivolumab treatment between October 2017 and September 2019. The frequency of irAEs and its treatment outcome were evaluated, and survival was compared during Nivolumab treatment. Results: The characteristics of 90 patients in this analysis were as follows: median age (range), 68 (36-85); male/female, 56/34; ECOG PS 0-1/≥2, 62/28; number of metastatic sites 1/≥2, 36/56; treatment line 3/≥4, 63/27. Median treatment cycle of nivolumab treatment was 3 (range 1-26). The overall response in 68 patients with target lesions was 6.3% (4/68), and the median PFS and OS was 1.5 and 4.3 months, respectively. IrAEs were observed in 8 patients (8.8%), including grade 4 pneumonitis, grade 2 or 3 adrenal insufficiency, and grade 2 hypothyroidism, encephalitis, and immune thrombocytopenia. Median time to onset of irAEs was 1.3 (range 0.6-10.5) months. Six were treated with systemic corticosteroid therapy, and all irAEs were relieved. The median PFS and OS were 4.7 months (95%CI, 1.2-9.3) and 12.2 months (95% CI, 3.2-not reached) in patient with irAEs, and 1.4 months (95%CI, 1.1-1.9) and 4.1 months (95%CI, 2.6-6.6) in those without, respectively. There was significant difference in the PFS (p=0.005) and OS (p=0.03). Conclusions: Nivolumab was effective and well tolerated even in clinical practice. Development of irAEs may be associated with better outcome of Nivolumab in patients with AGC.
Prognosis of Immune-related Adverse Events in Patients With Advanced Gastric Cancer Treated With Nivolumab or Pembrolizumab: A Multicenter Retrospective Analysis
