Gefitinib (ZD 1839, Iressa; AstraZeneca, London, UK) is an orally active, selective HER1-tyrosine kinase inhibitor (Wakeling et al, 2002), which has been shown to elicit objective responses in NSCLC cases, particularly in women nonsmokers with adenocarcinomas (Fukuoka et al, 2003; Kris et al, 2003). The gene discussed is EGFR; the disease is adenocarcinoma.