Comparison of first-line bevacizumab in combination with mFOLFOX6 or XELOX in metastatic colorectal cancer.

PURPOSE: Currently, there are several oxaliplatin combination regimens for first-line therapy of metastatic colorectal cancer (mCRC). In this study, we compared the survival outcomes of mCRC patients treated with bevacizumab in combination with either modified 5-FU/FA/oxaliplatin (mFOL- FOX6) or capecitabine/oxaliplatin (XELOX). METHODS: We designed a two-arm retrospective study of mCRC patients with adenocarcinoma of the colon or rectum who were treated with bevacizumab and either mFOLFOX6 or XELOX and who had complete clinical and treatment data. We analysed their therapeutic responses, adverse events, progression-free survival (PFS), and overall survival (OS), and then determined whether there were any statistically significant differences. RESULTS: A total of 131 patients (85 male; 65% and 46 female; 35%) were evaluated. Fifty-seven patients (43.5%) were treated with bevacizumab and mFOLFOX6 and 74 (56.5%) with bevacizumab and XELOX. The median PFS was 9.1 months (95% CI, 4.9-13.1) and 10 months (95% CI, 4.2-15.9) in the mFOLFOX6 and XELOX arms, respectively (p=0.610). The median OS was 29 months (95% CI, 21.6- 34.3) and 27.5 months (95% CI 20-38) in the mFOLFOX6 and XELOX arms (p=0.812), respectively. The most common reason for treatment withdrawal was disease progression (102 patients; 91%) and the most common grade 3-4 toxicity was neuropathy (≤14%). CONCLUSION: Our results show that XELOX is a safe and effective alternative to mFOLFOX6 when combined with bevacizumab as first-line treatment for mCRC patients.