Efficacy of second-line targeted agents in kras wild metastatic colorectal cancer patients who received prior targeted agent: First anti-epidermal growth factor receptor or vascular endothelial growth factor in right and left colon?

We aimed to investigate the impact of first biological agents on second-line biological agents in kras wild-type metastatic colon patients in right and left colon. The patients received anti-EGFR compared with anti-VEGF in right and left colon separately according to progression-free survival and overall survival in second line. A total of 84 patients were included in the study. In left colon, progression-free survival and overall survival were 9 and 14 months for anti-EGFR and 9 and 16 months for anti-VEGF in the second line. In right colon, progression-free survival and overall survival were 5 and 9 months for anti-EGFR and 4 and 6 months for anti-VEGF in the second line. Progression-free survival was higher in patients who received bevacizumab first followed by anti-EGFR than reverse sequencing in right colon. Overall survival was similar between two groups.