T790M Mutation Positive 2nd Line STandard of cAre Registry

The study is an observational prospective cohort study that plans to enroll approximately 200 patients worldwide. There are Epidermal Growth Factor Receptor (EGFR) mutations known to be associated with EGFR-targeted TKI sensitivity ( Ex19Del, L858R, L861Q, and G719X). Further tests on biopsied tissue or cytology at progression after treatment with an approved EGFR targeted TKI are used to determine positivity to T790M mutation. Primary objectives of the study are : * To estimate overall survival * To estimate disease progression (as assessed and defined by physician) * To estimate time on treatment by line of therapy * To describe time to subsequent therapies (or death) * To describe healthcare resource utilization patterns * To capture patient reported symptoms, functioning, and health-related quality of life (HRQoL) data using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 items (EORTC QLQ-C30) and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Lung Cancer 13 items (EORTC QLQ-LC13) * To describe the use of pemetrexed + cisplatin/carboplatin as the 2nd line treatment * To describe treatment patterns for 3rd line treatment and beyond