Association between antibiotic exposure and survival outcomes in hepatocellular carcinoma patients treated with immune checkpoint inhibitors: a systematic review and meta-analysis.

In 30 seconds

This systematic review and meta-analysis examined whether antibiotic exposure was associated with survival outcomes in patients with hepatocellular carcinoma (HCC) treated with immune checkpoint inhibitors. It included 12 retrospective cohort studies involving 3,643 patients, of whom 761 received antibiotics. Antibiotic exposure was associated with poorer overall survival (OS; HR = 1.29, 95% CI [1.17-1.41]); the association with poorer progression-free survival (PFS) was less robust in sensitivity analyses. Objective response and disease control rates did not differ significantly between exposure groups.

Key findings

• Antibiotic-exposed patients had shorter median OS than unexposed patients (12.2 months vs 17.0 months); pooled HR = 1.29, 95% CI [1.17-1.41].
• Median PFS was 5.2 months with antibiotic exposure and 7.5 months without; pooled HR = 1.27, 95% CI [1.01-1.59], but sensitivity analyses did not confirm robustness.
• No significant differences between groups were found for objective response rate or disease control rate.

Why it matters

The findings identify antibiotic exposure as a marker associated with poorer OS among patients receiving immune checkpoint inhibitors for HCC. This may be relevant when interpreting outcomes in this population, while the retrospective evidence cannot establish that antibiotics themselves cause worse survival. The less robust PFS association and absence of response-rate differences further warrant cautious interpretation.

What to keep in mind

All 12 included studies were retrospective cohorts, so confounding may explain some of the observed associations. The PFS finding was not robust in sensitivity analyses.