Surgical Treatment of Elderly Patients With cT1N0M0 Non-small Cell Lung Cancer Comparison Between Sublobar Resection and Lobectomy

Inclusion Criteria: * Aged 70 years or older * Preoperative criteria (contrast-enhanced Computed tomography scan) * Suspected non-small cell lung cancer * Clinical stage ⅠA, i.e. T1N0M0 (tumor diameter ≤3 cm, surrounded by visceral pleura, short-axis of lymph node \<1 cm or cold lymph nodes on PET scan) * The maximum diameter of consolidation of the maximum tumor diameter (consolidation/tumor ratio, C/T ratio) is no less than 0.5 in sub-solid lesions * Eligible for sublobar resection with sufficient margin * Intraoperative criteria * Histologically confirmed invasive NSCLC, i.e. NSCLC other than pre-invasive adenocarcinomas defined by The International Association for the Study of Lung Cancer (adenocarcinoma in situ, and minimally invasive adenocarcinoma) * Pathological exclusion of suspected lymph nodes involvement * Feasible to perform sublobar resection in terms of surgical margin requirement * General criteria * Must sign informed consent by the patient or his/her entrusted party * Must complete 4-year mortality index and comprehensive geriatric assessment(CGA) if necessary * The physiological reservation can tolerate lobectomy Exclusion Criteria: * Unable to comply with the study procedure * Past thoracic surgery history, except for diagnostic thoracoscopy * Malignant tumor history within the past 5 years, except for the following conditions: cured skin basal cell carcinoma, superficial bladder carcinoma, and uterine cervix cancer in situ * Any active systemic diseases including uncontrolled hypertension, unstable angina pectoris, newly onset of angina pectoris within recent 3 months, congestive heart failure (class II or plus of New York Heart Association, NYHA), myocardial infarction within recent 6 months, severe disease in the need of medication such as arrhythmia, liver, renal or metabolic diseases * Uncontrollable infections * Coexisting small cell lung cancer * Psychiatric diseases diagnosed * Other circumstances which is deemed inappropriate for enrollment by the researchers