Third-generation EGFR-TKI Treatment in Metastatic EGFR-mutant NSCLC

Inclusion criteria

• Pathologically confirmed non-small cell lung cancer;
• clinical stage IV (AJCC, 8th edition, 2017);
• EGFR sensitizing mutations (L858R or 19del);
• age≥18 years old;
• KPS score≥70;
• complete systemic imaging (including brain MRI) before third-generation EGFR-TKI treatment;
• received standard third-generation EGFR-TKI therapy (monotherapy or combined with brain radiotherapy);
• willing to cooperate with the follow-up after third-generation EGFR-TKI treatment;
• informed consent of the patient.

Exclusion criteria

• Multiple primary or metastatic tumors (except early skin cancer, cervical carcinoma in situ that has been treated radically, with no recurrence or progression for more than 5 years);
• Pregnant or lactating women who, as judged by the investigator, were not candidates for brain MRI;
• Uncontrolled epilepsy, central nervous system disease, or history of mental disorders, judged by the researcher to potentially interfere with the signing of the informed consent form or affect patient compliance.;
• patients without EGFR sensitive mutations or with unknown EGFR mutation status.

Withdrawal criteria

• The investigators considered that the patients had poor adherence to the study protocol.
• The patient withdrew informed consent and asked to withdraw.
• There was any safety reason (adverse event) considered by the investigator;
• Due to other underlying diseases, side effects, economic factors, and other reasons, patients did not receive regular doses of third-generation EGFR-TKI (continuous withdrawal time more than 1 week, cumulative withdrawal time more than 2 weeks, etc.).
• The patient was not followed up according to the protocol.
• Other circumstances in which withdrawal from the study was deemed necessary by the investigator.