Bevacizumab, a humanized monoclonal antibody against VEGF, selectively blocks VEGF binding to the VEGFR-1 and VEGFR-2 receptors, thereby inhibiting the tumor angiogenesis.[22] The addition of bevacizumab to 5-FU-based combination chemotherapy results in improvements in the overall response rate, PFS, and OS among mCRC patients.[10] This meta-analysis has clearly showed that compared with observation alone, bevacizumab-based maintenance therapy has a significant benefit in terms of PFS and has a trend toward prolonging OS in mCRC patients who benefit from first-line therapy. This evidence concerns the gene FLT1 and neoplasm.