Overall Survival and Progression-Free Survival Comparison of Bevacizumab Plus Chemotherapy Combination Regiment versus Chemotherapy Only Regiment in Previously Untreated Metastatic Colorectal Cancer: Systematic Review and Meta-Analysis

Abstract

BACKGROUND: Colorectal cancer is the third-most common cancer in the world, in which 15%–25% of patients already had metastatic colorectal cancer (mCRC) at the time of diagnosis. The overall survival (OS) of mCRC is poor with the use of chemotherapy. AIM: This systematic review and meta-analysis aim to examine the outcomes of OS and progression-free survival (PFS) of adding bevacizumab to different chemotherapy regiments compared to chemotherapy regiments only in the treatment of untreated mCRC. METHODS: Literature searching was done in databases such as PubMed, EBSCO, SCOPUS, and ScienceDirect. The primary outcome measured in this systematic review and meta-analysis was OS, while the secondary outcome was PFS. Hazard ratio (HR) was used as the main summary measure with 95% confidence interval (CI). Publication bias was measured using a funnel plot. RESULTS: Literature searching resulted in 11 selected studies, 9 selected for meta-analysis. Addition of bevacizumab showed significant better results in OS (HR 0.83, CI 95% 0.74–0.93; p = 0.002; I2 = 29%) and PFS (HR 0.62, 95% CI 0.51–0.75; p < 0.0001, I2 = 78%). CONCLUSION: The addition of bevacizumab to chemotherapy resulted in better OS and PFS in untreated mCRC. Further studies are needed to confirm PFS benefit from the combination of bevacizumab and chemotherapy due to significant heterogeneity.