Clinical experience investigation (CEI) is to be conducted to confirm the following to characterise safety and efficacy of Tagrisso Tablets in actual clinical use.

1. Incidence of adverse drug reactions (ADRs) in actual clinical use
2. Factors which may affect safety and efficacy of the product (especially analysis of the incidence and risk factors of interstitial lung disease (ILD) events)
3. Information of ADRs not expected from "Precautions for Use" of the package insert in Japan

Inclusion Criteria:

• patients treated with the product

Exclusion Criteria:

• No Account (NA)

All patients treated with the product will be enrolled in the investigation.