Background: Cetuximab (C) and panitumumab (P) increase response rate and survival in KRAS wild-type metastatic colorectal cancer (mCRC). We performed a meta-analysis of randomised controlled trials (RCTs) to assess their effect on overall response rate (ORR), the rate of radical resection (R0) and survival in patients with liver-limited initially unresectable mCRC.
Materials and methods: We searched MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials for RCTs comparing first-line chemotherapy plus or minus C or P and reporting data in patients with KRAS wild-type, unresectable liver-limited mCRC. Relative risks (RRs) with 95% confidence interval were calculated. Meta-analysis of hazard ratios (HRs) for progression-free and overall survival (PFS and OS) was also performed.
Results: Four RCTs involving 484 KRAS wild-type patients were included. Compared to chemotherapy alone, the addition of C or P significantly increased the ORR (RR 1.67, p = 0.0001), the R0 resection rate from 11% to 18% (RR 1.59, p = 0.04) and PFS (HR 0.68, p = 0.002), but not OS (p = 0.42).
Conclusions: The addition of C and P increased the R0 resection rate by 60% and reduced the risk of progression by 32% in patients with mCRC and unresectable liver-limited disease. This combination represents one of the preferred choices as conversion therapy in KRAS wild-type patients with unresectable liver metastases.