The results were similar to those reported by Loupakis et al. and Benavides et al., whereby rectal tumours were associated specifically with worse OS (32.1 months vs 38.3 months, P = 0.010) and ORR (49% vs 64%, P = 0.035) than left-sided colon tumours, while no significant differences in PFS (8.0 months vs 9.3 months, P = 0.136) and DCR (90% vs 90%, P = 0.949) were seen in the first-line anti-EGFR treatment group [20, 21]. This evidence concerns the gene EGFR and colonic neoplasm.