As EGFRvIII heterodimerises with wtEGFR, is constitutively phosphorylated and activates AKT and to a lesser extent ERK, we hypothesised that the chance of finding EGFRvIII-positive tumours was largest in this subgroup (Montgomery et al, 1995; Li et al, 2004; Luwor et al, 2004). The gene discussed is AKT1; the disease is neoplasm.