This meta-analysis used the database including PubMed, Medline, Cochrane Library, CNKI, Chinese-Cqvip, and Wanfang for randomized controlled trials (RCTs) to investigate the clinical effectiveness for combining
cetuximab treatment with
chemotherapy for treating metastatic
colorectal cancer (mCRC). A total of 12 RCTs involved 7,108 patients with mCRC were included. The patients received
chemotherapy with (3,521 cases) or without
cetuximab (3,587 cases). Outcomes were overall survival (OS), progression-free survival (PFS), disease control rate (DCR), overall response rate (ORR), odd ratio (OR), and risk ratio (HR). Our results showed that the
chemotherapy alone group has shorter OS, PFS, and ORR than the
chemotherapy plus
cetuximab group, with significant differences (PFS:HR = 0.77, 95% CI = 0.72-0.82, P < 0.00001; OS:HR = 0.88, 95% CI = 0.79-0.99, P = 0.03; ORR:OR = 1.79, 95% CI = 1.30-2.47; P = 0.0003). Results of subgroup analysis showed that
cetuximab treatment prolonged PFS and OS in KRAS wild-type patients, with statistically significant differences (PFS:HR = 0.79, 95% CI = 0.65-0.95, P = 0.01; OS:HR = 0.85, 95% CI = 0.74-0.98, P = 0.02). Combining
cetuximab with
chemotherapy, the PFS and OS of wild-type KRAS patients and the ORR of all patients were significantly improved.