Abstract: Objective To assess the impact of nonsteroidal anti-inflammatory drugs (NSAIDs) on clinical outcomes of patients receiving anti-PD-1 immunotherapy for hepatocellular carcinoma. Methods We conducted a retrospective study among 215 patients with primary liver cancer receiving immunotherapy between June, 2018 and October, 2020. The patients with balanced baseline characteristics were selected based on propensity matching scores, and among them 33 patients who used NSAIDs were matched at the ratio of 1∶3 with 78 patients who did not use NSAIDs. We compared the overall survival (OS), progression-free survival (PFS), and disease control rate (DCR) between the two groups. Results There was no significant difference in OS between the patients using NSAIDs (29.7%) and those who did not use NSAIDs (70.2% ). Univariate and multivariate analyses did not show an a correlation of NSAIDs use with DCR (univariate analysis: OR=0.602, 95% CI: 0.299- 1.213, P=0.156; multivariate analysis: OR=0.693, 95% CI: 0.330-1.458, P=0.334), PFS (univariate analysis: HR=1.230, 95% CI: 0.789-1.916, P=0.361; multivariate analysis: HR=1.151, 95% CI: 0.732- 1.810, P=9.544), or OS (univariate analysis: HR=0.552, 95% CI: 0.208-1.463, P=0.232; multivariate analysis: HR=1.085, 95% CI: 0.685-1.717, P=0.729). Conclusion Our results show no favorable effect of NSAIDs on the efficacy of immunotherapy in patients with advanced primary liver cancer, but this finding still needs to be verified by future prospective studies of large cohorts.

Key words: immunotherapy; primary liver cancer; nonsteroidal anti-inflammatory drugs