Tumor sidedness and efficacy of first-line therapy in patients with RAS/BRAF wild-type metastatic colorectal cancer: A network meta-analysis

•This meta-analysis compares first-line therapy efficacy for KRAS, RAS, BRAF WT mCRC.•Selected RCTs compared chemotherapy plus mAb combination against chemotherapy alone.•SUCRA values were used to identify the best possible therapy in the meta-analysis.•Cetuximab and panitumumab are the most effective treatments for left-sided mCRC.•Bevacizumab is a more optimal choice for right-sided mCRC. We conducted a systemic search of several databases for randomized controlled trials (RCTs) that reported efficacy and safety outcomes of drugs for left-sided and right-sided metastatic colorectal cancer (mCRC), to identify the best available treatment. A network meta-analysis with mixed comparisons was created to interpret the best treatment option using the surface under the cumulative ranking curve. In the left-sided rat sarcoma (RAS) wild-type (WT) mCRC patients, bevacizumab, panitumumab, or cetuximab with chemotherapy groups showed a significantly better objective response rate than the chemotherapy alone group. The progression-free survival (PFS) and overall survival were better with panitumumab or cetuximab with chemotherapy than with chemotherapy alone. In the right-sided RAS WT mCRC patients, PFS for bevacizumab with chemotherapy was significantly better than that for cetuximab with chemotherapy. Cetuximab, closely followed by panitumumab, is the most effective treatment in left-sided RAS WT mCRC. Bevacizumab is more effective in right-sided mCRC.