The ”Panitumumab Randomized trial In combination with chemotherapy for Metastatic colorectal cancer to determine Efficacy” PRIME study and the “Cetuximab Combined with Irinotecan in First-Line Therapy for Metastatic Colorectal Cancer” CRYSTAL study were the phase III trials, which demonstrated the efficacy of the combination of anti-EGFR plus chemotherapy versus chemotherapy alone. This evidence concerns the gene EGFR and colorectal cancer.