Role of the C-reactive protein-albumin ratio in predicting survival after breast cancer: A systematic review and meta-analysis

Abstract

Objective: This review aimed to evaluate the association between C-reactive protein-albumin ratio (CAR) and survival outcomes in patients with breast cancer.

Methodology: Databases of PubMed, Embase, Scopus, and Web of Science were searched up to 3rd November 2025. Included studies involved adult patients with histologically confirmed breast cancer that reported hazard ratios (HRs) and 95% confidence intervals (CIs) for either overall survival (OS) or disease-free survival (DFS).

Results: Six studies involving 2,427 patients were included. The pooled analysis demonstrated that elevated CAR was significantly linked with worse OS (HR = 2.66, 95% CI 1.64-4.31) and poorer DFS (HR = 2.39, 95% CI 1.50-3.82). Subgroup analyses revealed consistent associations across study design, cancer subtype, stage, country, and follow-up duration. Meta-regression showed that CAR cut-off value did not significantly influence the effect size for either OS or DFS. Sensitivity analyses indicated stable results.

Conclusions: An elevated CAR may be associated with poorer OS and DFS in breast cancer. Given the scarce evidence, further research is needed to provide robust results.

Registration No: PROSPERO database (CRD420251181780).