A Randomised Controlled Phase II Trial of the Combination of XELOX with Thalidomide for the First-line Treatment of Metastatic Colorectal Cancer

OBJECTIVE: To evaluate the efficacy and safety of the combination of XELOX regimen (oxaliplatin plus capecitabine) with thalidomide for the first-line treatment of metastatic colorectal cancer (MCRC). METHODS: All of the 89 patients with MCRC who fulfilled eligibility criteria were randomly assigned to treatment group (n=44) and control group (n=45). The treatment group received a combination of XELOX with thalidomide and the control group received XELOX alone. Each patient received at least 2 cycles of treatment (1 cycle=21 d). The primary endpoint was progression-free survival (PFS) and the secondary endpoints were objective response rate (ORR) as well as disease control rate (DCR). Drug safety and quality of life were also assessed. RESULTS: The median PFS of the treatment and control groups were 5.6 and 5.2 months, respectively. The difference did not have a statistical significance (P=0.307). The ORRs of the two groups also had no statistical difference (34.1% vs. 26.7%, P=0.446). The addition of thalidomide to XELOX significantly improved the DCR (63.6% vs. 42.2%, P=0.043). Among 24 patients with hepatic metastasis in the treatment group, 2 patients satisfied the surgical criteria after treatment but none of 23 patients in the control group did. Grade 3 or 4 constipation in patients treated with thalidomide was significantly increased (20.5% vs. 4.4%, P=0.022) but didn’t result in treatment interruption. The rate of lethargy was increased but the difference between the two groups had no statistical significance (13.6% vs. 4.4%, P=0.130). The quality of life had no statistical difference between the two groups. CONCLUSIONS: The combination of XELOX with thalidomide for the first-line treatment of MCRC was well tolerated. Statistically significant improvement was achieved for the DCR but not for PFS.