Lung adenocarcinoma belongs to non-small cell lung cancer according to the histologic classification criteria, and there are statistics that the 5-year survival rate of stage II non-small cell lung cancer is about 55%. Lung adenocarcinoma is the most common type of lung cancer, which mainly originates from bronchial mucous glands and may occur in the central airways or tiny bronchi. It can grow outside the airways or spread along the alveolar walls, forming masses or nodules at the margins of the lungs. Infiltration or metastasis through the bloodstream occurs early, and it tends to involve the pleura and cause pleural effusion. Stage II lung adenocarcinoma indicates that the maximum diameter of the tumor is over 4cm, or it involves the chest wall, pericardium, phrenic nerve and any other organs, or the tumor cells are relatively small but lymph node metastasis has occurred. In this case, early treatment is needed, and patients who can be surgically resected are recommended to undergo surgery, striving for radical resection, and combining with radiation therapy or chemotherapy if necessary. Lung adenocarcinoma patients can effectively improve their prognosis after active comprehensive treatment, about 55% of patients can survive for more than 5 years, but more than half of patients can survive for less than 5 years after treatment.