We found that PDOs obtained from patients with a left-sided RAS/BRAF-WT tumor (n = 9) were more sensitive to EGFR inhibitor panitumumab, compared with PDOs obtained from patients with right-sided and/or RAS/BRAF-mutant tumors (n = 15; median-normalized GRAUC, 0.59 vs. 0.81; P = 0.012; Fig. 5C). This evidence concerns the gene BRAF and neoplasm.