EGFR and non-small cell lung carcinoma: Patients with exon 19 harboring deletions were found to have longer survival following treatment with gefitinib or erlotinib compared with those having L858R mutations in NSCLC [32,33]; however, Marks et al. reported no difference in survival between exon 19 deletions and L858R mutations in the absence of EGFR targeted therapy [34].