Nonetheless, a recent report suggested that the use of cetuximab or bevacizumab as a first-line therapy was associated with survival benefit among patients with p.G13D-mutated tumours, whereas KRAS codon 12 mutations were associated with resistance to cetuximab among chemotherapy-refractory CRC patients [81, 82, 169]. This evidence concerns the gene KRAS and colorectal carcinoma.