Visceral fat and clinical outcome in patients receiving first-line chemotherapy with bevacizumab for metastatic colorectal cancer

Visceral fat produces angiogenic factors such as vascular endothelial growth factor that promote tumoral growth. However, its influence on outcome for patients with advanced cancer treated with anti-angiogenic agents is controversial. The aim of this study was to determine whether visceral fat volume, visceral fat area and body mass index are associated with outcome in patients receiving first-line bevacizumab-based treatment for metastatic colorectal cancer. This multicenter prospective study included 103 patients with metastatic colorectal cancer who received first-line bevacizumab-based chemotherapy. Computed tomography was used to measure visceral fat volume and visceral fat area. Endpoints were tumoral response at 2 months, progression free survival and overall survival. Visceral fat volume and visceral fat area, but not body mass index, were significantly associated with better outcome. Using sex-specific median values progression free survival was significantly longer in patients with high visceral fat volume (13.2 versus 9.4 months; p=0.0043). In the same way, high visceral fat volume and visceral fat area were associated with a significantly better overall survival: 31.3 versus 20.5 months (p=0.0072) and 29.3 versus 20.5 months (p=0.0078), respectively. By multivariate analysis, visceral fat volume was associated with longer progression free survival and overall survival. This study demonstrates that a high visceral fat volume is associated with better outcome in patients receiving first-line bevacizumab-based chemotherapy for metastatic colorectal cancer.