Low visceral fat content is a negative predictive marker for bevacizumab in metastatic colorectal cancer

Aim: This study aimed to clarify the predictive impact of visceral fat on response to bevacizumab in patients with metastatic colorectal cancer (mCRC). Patients and Methods: Pretreatment computed tomography was used to measure visceral fat area (VFA) and patients with mCRC receiving first-line chemotherapy with/without bevacizumab were divided by median VFA value into two groups: high VFA and low VFA. Results: In the bevacizumab-treated group, patients with low VFA had significantly shorter overall survival (OS) than patients with high VFA in univariate (median=21.1 vs. 38.9 months; hazard ratio=1.70, 95% confidence interval=1.06-2.70, p=0.03) and multivariate analysis (hazard ratio=1.85, 95% confidence interval=1.15-3.03, p=0.01). No significant differences were seen in OS between groups treated with chemotherapy alone. The VFA had a marginally significant modifying effect on the relationship between bevacizumab and OS (p for interaction=0.07). Conclusion: Our findings provide the first evidence that a low VFA might be a negative predictive marker for response to bevacizumab in patients with mCRC.