Current clinical data is sufficiently compelling that K-Ras mutation testing to facilitate the selection of patients most likely to benefit from anti-EGFR therapy is increasingly recommended in clinical practise (McNeill, 2008; van Krieken and Tol, 2009), and has resulted in a recent formal recommendation from the National Comprehensive Cancer Network that patients with K-Ras tumour mutations should not be treated with cetuximab or panitumumab (McNeill, 2008). The gene discussed is EGFR; the disease is neoplasm.