Age older than 18 years and under 75 years

Histologically and cytologically proven non-small Cell Lung Cancer

Clinical stages Ⅲ \~ Ⅳ

Not receive any anti-tumor treatment

Eastern cooperative oncology group performance status (ECOG PS) =1\~2

Estimated survival time more than 3 months

EGFR-TKI treatment for first-line or second-line

Voluntary to participate in this clinical trial and sign the consent form

EGFR Mutation Detection From Advanced NSCLC Patient Tissue and Plasma in EGFR-TKI Treatment