This nationwide, multicenter, prospective, randomized open phase III study of cVATS (complete Video-assisted Thoracoscopic Surgery) segmentectomy versus Lobectomy for stage IA non-small cell lung cancer (NSCLC) patients with Lung adenocarcinoma in situ or with microinvasion, is aiming to evaluate the relapse free survival and 5 year overall survival (OS) rate of two types of surgery. Patients are randomized to 1 of 2 treatment arms.