Importantly, a fraction of NSCLC patients have displayed partial response to erlotinib despite lack of EGFR mutations and the identification of molecular biomarkers of response would be of great clinical value to prospectively select those EGFR-WT patients who are likely to benefit from erlotinib therapy.16, 17, 18, 19. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.