This study is a prospective, national, multi-center, non-interventional study. The main purpose is to explore the initial adjuvant treatment pattern after radical resection for early-stage NSCLC patients with EGFR Mutation-Positive in the real world. The secondary purpose was to observe the postoperative follow-up treatment pattern and its subgroups (based on different EGFR mutation status and different clinical stages).

About 2,000 eNSCLC patients who received radical resection from about 50 research centers across the country will be included in this study, and will be followed up to 2 years after enrollment according to the actual clinical situation. The analysis method of this study is mainly based on descriptive statistics. The information about the human genetic resources of the subjects to be collected includes: demography, physical examination, WHO fitness status, medical history, smoking history, disease characteristics, surgical information, initial and follow-up adjuvant treatment pattern, laboratory tests, survival status, and adverse events related to gefitinib/osimertinib, serious adverse events/non-severe ADR, measures taken for adverse events, outcome of adverse events.

Inclusion Criteria:

1. Informed consent signed;
2. Newly confirmed EGFR Mutation-Positive NSCLC confirmed by histopathology except for cytology;
3. Receiving or not receiving neoadjuvant treatment before surgery;
4. Patients with stage I-III NSCLC undergo confirmed radical R0 resection;

Exclusion Criteria:

1. Patients who currently or have previously participated in any other anti-tumor clinical studies;
2. Patients with NSCLC who have received any systemic anti-cancer therapy as the main treatment in the past. Cytotoxic therapy, targeted therapy (tyrosine kinase inhibitors or monoclonal antibodies) and immunotherapy included except for the use of neoadjuvant therapy;
3. Patients who have received adjuvant therapy before enrollment.
4. Patients with stage I-III NSCLC whose surgical resection cannot be confirmed.
5. Patients assessed by the investigator as unfit for enrollment, such as neurological disorders or metabolic disorders, physical examination or laboratory examination suspected that the patient has a possible disease, or has contraindications to the use of study drugs, or has treatment-related complications High risk etc.

Continuously enroll all patients with early-stage (stage I-III), histopathologically confirmed, and EGFR mutation-positive NSCLC after R0 resection