Impact of bevacizumab on clinical outcomes and its comparison with standard chemotherapy in metastatic colorectal cancer patients: a systematic review and meta-analysis.

Background: Advances in targeted therapies have expanded the treatment options for colorectal cancer (CRC), allowing for more tailored and effective approaches to managing the disease. In targeted therapy, Bevacizumab is a commonly prescribed anti-VEGF monoclonal antibody that has a direct anti-vascular impact in cancer patients. Vascular Endothelial Growth Factors (VEGFs), especially VEGF-A, are significant agents in promoting tumour angiogenesis.

Objective: To assess the impact of adding Bevacizumab to chemotherapy on progression-free survival (PFS) and overall survival (OS) in patients with metastatic colorectal cancer.

Methodology: Comprehensive searches have been performed on electronic databases such as PubMed, and Google Scholar using the following terms: colorectal cancer, adenocarcinoma, Bevacizumab, chemotherapy, and monoclonal antibody.

Results: In the meta-analysis, 16 out of the 24 included studies were analysed. In the final analysis, incorporating Bevacizumab with chеmothеrapy demonstrated favourable outcomes for OS with a hazard ratio (HR = 0.689,95%CI: 0.51-0.83, I² = 39%, p <0.01) and for PFS with a hazard ratio (HR = 0.77 95% CI: 0.60-0.96, I² = 54%, p < 0.01). The subgroup analysis of PFS, categorised by study dеsign (prospеctivе vs rеtrospеctivе), reveals that the Hazard Ratio (HR = 0.82, 95% CI: 0.62-0.97, I² = 21%, p < 0.01) and for OS with a hazard ratio (HR = 0.73, 95% CI: 0.52-0.86, I² = 17%, p < 0.01).

Conclusion: Our findings indicate that combining Bevacizumab with chemotherapy enhances clinical outcomes and results in a significant increase in PFS and OS in patients with metastatic colorectal cancer. Positive outcomes are demonstrated by a substantial 23% increase in PFS and 31% increase in OS in patients with metastatic colorectal cancer who undergo Bevacizumab in conjunction with chemotherapy.