The association between antibiotics use and outcome of cancer patients treated with immune checkpoint inhibitors: A systematic review and meta-analysis

Objective: This meta-analysis was to evaluate the impact of antibiotics use on survival of cancer patients with immune checkpoint inhibitors (ICIs). Methods: Electronic databases including Pubmed, Emabse, and the Cochrane library were searched. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Results: A total of 20 retrospective studies were included. The median OS (7.9 months versus 17.65 months) and PFS (2.4 months versus 4.4 months) of the antibiotics use group were shorter compared to control group. Meta-analysis also showed that the risks of death (HR = 1.90, 95 % CI: 1.55-2.34; P<0.01) and disease progression (HR=1.53, 95 % CI: 1.30-1.79; P<0.01) in antibiotics positive group were significantly higher than that of the negative group. The prognostic role of antibiotics use was still significant regardless of cancer types and timing of antibiotics (P<0.01 for all). Conclusion: Use of antibiotics may be associated with worse outcomes in cancer patients treated with ICIs.