The European Medicines Agency (EMA) approval for gefitinib treatment in advanced NSCLC in patients with EGFR mutation-positive (M+) tumours was based largely on evidence from the Iressa Pan-Asia Study (IPASS) [5], together with a comprehensive review of gefitinib data in EGFR M+ NSCLC patients across lines of therapy. This evidence concerns the gene EGFR and non-small cell lung carcinoma.