Prognostic role of C-reactive protein to albumin ratio in cancer patients treated with immune checkpoint inhibitors: a meta-analysis

Background There are numerous articles investigating whether C-reactive protein to albumin ratio (CAR) is significant for predicting prognosis of cancer cases receiving immune checkpoint inhibitors (ICIs), whereas the results were inconsistent. We thus retrieved the literature and conducted the present meta-analysis for clarifying relation of CAR with survival outcomes among ICI-treated cancer patients.Methods Through search against the Web of Science, PubMed, Cochrane Library, and Embase databases was carried out. The search was updated on 11 December 2022. This work later determined the combined hazard ratios (HRs) together with 95% confidence intervals (CIs) for estimating CAR for its prognostic efficiency for overall survival (OS) and progression-free survival (PFS) in cancer patients receiving ICIs.Results A total of 11 studies consisting of 1,321 cases were enrolled into the present meta-analysis. As revealed by combined data, the increased CAR level markedly predicted dismal OS (HR = 2.79, 95% CI = 1.66-4.67, p < 0.001) together with shortened PFS (HR = 1.95, 95% CI = 1.25-3.03, p = 0.003) among carcinoma cases using ICIs. The prognostic effect of CAR was not influenced by clinical stage or study center. Our result reliability was suggested by sensitivity analysis and publication bias test.Conclusions High CAR expression showed marked relation to worse survival outcomes among ICI-treated cancer cases. CAR is easily available and cost effective, which can be the potential biomarker for selecting cancer cases benefiting from ICIs.

Automated summary

This meta-analysis investigated the association between C-reactive protein to albumin ratio (CAR) and the prognosis of cancer patients receiving immune checkpoint inhibitors (ICIs). The results indicated that high CAR expression was associated with worse survival outcomes. CAR is a potential biomarker for selecting cancer patients who would benefit from ICIs, as it is easily accessible and cost-effective.