Icotinib as Neoadjuvant and Adjuvant Therapy in EGFR-mutant Stage IIIB or Oligometastasis Non-small Cell Lung Cancer

Inclusion Criteria: * Histology or cytology confirmed Non-small Cell Lung Cancer; EGFR mutation (EGFR 19del and/or 21L858R) detected by tumor tissue biopsy of primary lesion or metastatic lesion or plasma ctDNA * No previous anti-tumor treatment such as surgery, chemotherapy, radiotherapy or biological therapy * Stage IIIB or IV Oligometastasis Non-small Cell Lung Cancer. (a) stage IV Oligometastasis: the metastasis organ mainly include: 1. adrenal metastasis which can be potentially resected by surgery or radically treated by SRS radiotherapy; 2. brain metastasis which can be potentially resected by surgery or radically treated by SRS radiotherapy. At the same time, the primary lesion of the lung can be completely removed, which should be T1-2, N0-1 or T3, N0. (b) stage IIIB (T1-3, N3): it is limited to patients who are unsuitable or refuse to accept pulmonary primary lesion radiotherapy. It only include subclavian lymph node or anterior scalenus lymph node metastasis (mediastinal lymph node metastasis is excluded by PET-CT). The metastasis lesion should be single or less than 3, its diameter is no more than 3 cm and can be potentially resected. * Sufficient tumor histological specimens (non-cytology) for molecular marker analysis * At least one lesion with measurable diameter and its longest diameter is large than 10 mm by CT measurement Exclusion Criteria: * Previous systemic anti-tumor treatment of Non-small Cell Lung Cancer, including cytotoxic drug therapy, targeted drug therapy (tyrosine kinase inhibitors or monoclonal antibodies) and experimental treatment, etc * Previous local radiotherapy of Non-small Cell Lung Cancer * Be allergic to any component of Icotinib tablet (Conmana) * Other cancers within five years prior to the treatment of this study. Except for cervical carcinoma, basal cell carcinoma and bladder epithelial neoplasm (including Ta and Tis) * Any instable systemic disease, including: active infection, high blood pressure out of control, unstable angina, onset of angina pectoris within the past 3 months, congestive heart failure, myocardial infarction, severe arrhythmia, liver, kidney or metabolic disease * Previous interstitial lung disease, drug-induced interstitial disease, radiation pneumonia requiring hormone therapy or any active intersexual lung disease with clinical evidence * Idiopathic pulmonary fibrosis detected by CT scan at baseline; * Not fully controlled eye inflammation or infections, or any condition that may lead to the above eye diseases * Human immunodeficiency virus infection * Patients undergoing major surgery or severe trauma within 2 months prior to the first use of the experimental drug * Patients with Small Cell Lung Cancer * Pregnant or lactating women * Neurological or psychiatric disorders history, including epilepsy or dementia * Other situations not appropriate to enter the group considering by the investigators