Review the tumor markers of lung cancer, CT of chest and abdomen, MRI of head after early stage lung adenocarcinoma surgery. 1. Tumor markers of lung cancer: tumor markers are carcinoembryonic antigen, neurospecific enolase, cytokeratin 19 fragment, which can initially determine whether the tumor has progressed or recurred. 2. Thoracic and abdominal CT: postoperative follow-up of thoracic and abdominal CT can clarify whether there are recurrent lung lesions and metastasis of abdominal organs. 3. Cranial MRI: Lung adenocarcinoma is prone to brain metastasis, so it is necessary to review cranial MRI after surgery to check whether there are brain metastases. After surgery for early stage lung cancer, no matter whether it is cured or not, it is necessary to go to the hospital for regular checkups in order to find out the disease at an early stage and treat it actively.