This is a multicenter single arm study, with an aim to assess the effects of adjuvant icotinib among EGFR mutant stage I lung adenocarcinoma patients, who have high-risk pathological features of recurrence.

Inclusion Criteria:

• Male or female, at least ≥ 18 years，and ≦ 80 years

• Lung adenocarcinoma.

• Stage I disease(IA or IB), based on TNM8 classification.

• There is at least one of the following high-risk factors:

  1. pathologically confirmed vascular invasion positive;
  2. pathologically confirmed lung adenocarcinoma containing solid or micropapillary or complex gland histology, with a percentage > 20%;
  3. pathologically confirmed invasive tumor size > 2 cm;
  4. pathologically confirmed visceral pleural involvement (T2a).

• Started adjuvant therapy in this study 4-6 weeks after complete resection without any previous antitumor therapy.

• A tumour which harbours one of the 2 EGFR mutations (Ex19del, L858R) ,without KRAS mutation

• World Health Organization performance status of 0 or 1.

• Bood routine: HB > 80g/L; ANC > 1.0x109/L; PLT > 50x109/L.Blood biochemistry： ALT and AST < 2.5 times the upper limit of normal; Crea < 1.5 times the upper limit of normal.

• Good adherence to follow-up.

• During the trial and for 3 months after the trial，Participants must be using highly effective contraceptive measures.

Exclusion Criteria:

• Prior treatment with any anticancer therapy for NSCLC (including chemotherapy, radiotherapy, immunotherapy, and EGFR-TKIs).
• Local radiotherapy.
• Patients with cancers other than NSCLC (except cured cervical carcinoma in situ, cured basal cell carcinoma and bladder epithelial tumors) within 5 years prior to the start of treatment in this study.
• Any unstable systemic disease (including active infection, uncontrolled hypertension, unstable angina, angina pectoris beginning within the last 3 months, congestive heart failure, myocardial infarction occurring within 6 months prior to enrollment, severe arrhythmia requiring medication, liver, kidney or metabolic disease).
• Any clinical evidence suggestive of active interstitial lung disease.
• An eye inflammation or eye infection that is not fully controlled, or any condition that could lead to one of these eye conditions.
• Known human immunodeficiency virus (HIV) infection.
• Known hypersensitivity to EGFR-TKI drugs or related components.
• Mixed small cell and non-small cell cancer history.
• Substance abuse, or illnesses such as psychological or psychiatric disorders that may interfere with study compliance.
• Patients with epilepsy requiring medication (e.g. steroids or anti-epileptic drugs).
• Other conditions deemed unsuitable for enrollment by the investigator.