EGFR and neoplasm: Thus, the lack of EGFR mAb response observed in the setting of mutant KRAS (Schubbert et al, 2007; Amado et al, 2008) extends to other common mutations that deregulate cellular signalling pathways, especially BRAF and probably even PIK3CA. Lower PFS did not translate into differences in OS between patients with WT or mutant KRAS and PIK3CA alleles in the primary tumour.