Association between bevacizumab-related chemotherapy regimens and serum vascular endothelial growth factor-A165b level in patients with metastatic colorectal cancer.

OBJECTIVE: Colorectal cancer is the third most common cancer and the third leading cause of cancer-related death. Bevacizumab improves survival for metastatic colorectal cancer patients with chemotherapy, but no proven predictive markers exist. The aim was to investigate the possible predictive value of vascular endothelial growth factor (VEGF)-A165b levels in this setting. PATIENTS AND METHODS: Pre-treatment serum samples and response evaluations were available from 60 patients. Patients were randomized to bevacizumab + FOLFIRI (BF arm) or placebo + FOLFIRI (PF arm). The expression serum VEGF-A165b levels were analysed by an ELISA. Group comparisons were made using the Wilcoxon test and baseline characteristics of groups were compared using χ2 tests.
RESULTS: Patients with low baseline VEGF-A165b levels are more likely to have an increased probability of response with the addition of bevacizumab (32.3% response on BF arm versus 8.2% on PF arm, p = 0.01) than those with high VEGF-165b levels (27.5% response on BF arm versus 28.6% on PF arm, p = not significant).
CONCLUSIONS: In this correlative evaluation, pretreatment serum VEGF-A165b levels were predictive for bevacizumab-based treatment benefit.

RCT Entities:   Population Interventions Outcomes