Purpose: Inconsistent results on the prognostic significance of C-reactive protein to albumin ratio (CAR) in colorectal cancer patients have been reported. This meta-analysis sought to assess the prognostic value of pretreatment CAR for survival outcomes in colorectal cancer patients.
Methods: We conducted a systematic literature search of PubMed and Embase databases until February 16, 2019. Observational studies investigating the prognostic role of pretreatment CAR for survival outcome in patients with colorectal cancer were included. Outcome measures included overall survival (OS), disease-free survival (DFS), or progression-free survival (PFS). Pooled hazard ratio (HR) with 95% confidence interval (CI) was utilized to summarize the prognostic significance of CAR for patient survival.
Results: Nine retrospective studies involving 2492 colorectal cancer patients were identified. A fixed-effect model meta-analysis showed that high pretreatment CAR was an independent predictor of poor OS (HR 2.25; 95% CI 1.84-2.76) and DFS (HR 2.49; 95% CI 1.43-4.33). On the other hand, no significant association was observed between high CAR and PFS (HR 1.71; 95% CI 0.44-6.60). The predictive values of OS with high pretreatment CAR caused no significant changes in different sample sizes, countries, cut-off values of CAR, treatment methods, and study quality of subgroups.
Conclusion: This meta-analysis suggests that CAR may be a powerful prognostic indicator for colorectal cancer prognosis. High pretreatment CAR is associated with poor OS and DFS in patients with colorectal cancer.
Keywords: C-reactive protein/albumin ratio; Colorectal cancer; Disease-free survival; Meta-analysis; Overall survival.