Two large, randomised clinical trials of EGFR TKI monotherapy in second-line/third-line NSCLC have been retrospectively analysed for biomarkers that may predict response and survival benefit to EGFR TKIs: BR.2116, 17 and ISEL.18 Data from both trials supported EGFR FISH status as a potential predictive marker of tumour response and patient survival to TKIs. The gene discussed is EGFR; the disease is neoplasm.