Effect of VEGF-1 Expression in Colorectal Cancer on Clinic Pathological Outcome and Impact of Anti VEGF in Metastatic CRC with Intact Primary Tumor

Background: Colorectal cancer (CRC) is third leading cause of cancer mortality. About 60% of patients had already developed metastasis at the time of diagnosis. Tumor growth and metastasis are dependent on angiogenesis. Evidence from preclinical and clinical studies indicates that vascular endothelial growth factor (VEGF) is the predominant antigenic factor in CRC. There is an unmet need for predictive markers for the antiangiogenic agent bevacizumab in metastatic colorectal cancer (mCRC). We aimed to assess whether the location of the primary tumor is associated with bevacizumab effectiveness when combined with Chemotherapy (FOLFOX) in the first-line treatment of patients with mCRC.

Patients and Methods: A group of 17 consecutive patients with mCRC from the general community treated from January 2018 to October 2019 with FOLFOX and bevacizumab as standard first-line therapy was compared with a group of 17 patients treated with FOLFOX from January 2018 to October 2019. Main outcome measures were progression-free survival (PFS). Differences in survival outcome were analyzed.

Results: Patients treated with FOLFOX and bevacizumab with primary tumors originating in the left colon and rectum had a significantly better outcome than patients with primary tumors originating from the right colon. This difference was confirmed in multivariate analyses after adjustment for other potentially prognostic factors. For patients treated with FOLFOX, there was no association between primary tumor location and outcome, neither in unadjusted nor adjusted analyses.

Conclusions: The addition of bevacizumab to FOLFOX in first-line treatment of patients with mCRC improved progression free survival than patients treated by FOLFOX alone.