Based on retrospectively collected data and post hoc analyses of large phase III studies, the European Medicines Agency has restricted the use of cetuximab to the treatment of patients with KRAS codons 12 and 13 wild-type disease (about the 60% of the overall population; EMEA, 2008) and the American Society of Clinical Oncology has similarly recommended in a recent provisional clinic opinion not to administer anti-EGFR moAbs to patients with KRAS codons 12 or 13 mutated tumours (Allegra et al, 2009). This evidence concerns the gene KRAS and neoplasm.