The odds ratio of ORR favored anti-EGFR-based chemotherapy regardless of the primary tumor location (OR: 1.49, 95% CI=1.16–1.0, p=0.002 for left-sided tumor; OR: 1.2, 95% CI= 0.77–1.87, p=0.432 for right-sided tumor) compared to anti-VEGF-based chemotherapy. Here, EGFR is linked to neoplasm.