Several phase II studies have shown the efficacy of ERBB2 blockade (trastuzumab in combination with pertuzumab, lapatinib or tucatinib) in patients with ERBB2-amplified mCRC [23,24,25], while ERBB2 mutations have been associated with the response to ERBB2 blockade in patient CRC xenografts [26]. This evidence concerns the gene ERBB2 and colorectal carcinoma.