K-Ras mutation status has recently been convincingly associated with response to the new generation EGFR antagonists cetuximab (Erbitux) and panitumumab (Vectibix), where response is preferentially observed in wt K-Ras tumours (Lievre et al, 2006; Benvenuti et al, 2007; Khambata-Ford et al, 2007; Freeman et al, 2008; Karapetis et al, 2008; Ramos et al, 2008; Loupakis et al, 2009; Van Cutsem et al, 2009). This evidence concerns the gene EGFR and neoplasm.