1.Chest X-ray (frontal and lateral chest X-ray) can be used for the initial screening of lung, chest wall, rib cage and pleural cavity diseases. 2, Chest CT plain and enhanced examinations are the most valuable non-invasive examinations for diagnosing chest diseases, and can clarify the presence of almost most lung, esophageal and mediastinal diseases. Spiral CT thin layer scan can detect small nodules or hairy glass-like lesions of a few millimeters, which is significant for the detection of early lung cancer. 3.Magnetic resonance imaging (MRI) can evaluate the adjoining of chest tumors and the relationship with blood vessels in multiple directions. 4.Bronchoscopy can perform brush cytology, bite biopsy, local lavage, etc., which is more meaningful for central type lung cancer. 5.ECT bone imaging can detect bone metastases earlier. 6.Mediastinoscopy needs general anesthesia to complete, and mediastinal lymph node biopsy and staging can be performed. 7.PET examination can detect systemic metastases and make preoperative staging more accurate. 8.Other examinations such as sputum exfoliation cytology, percutaneous lung aspiration cytology. 9.Thoracocentesis cytology examination helps to obtain the pathological basis of lung tumor before surgery. 10.Esophageal barium swallow imaging: It can be used to find out the relative position of esophageal lesions in the chest, the length of lesions, the degree of obstruction, etc. 11.Gastroscopy: It can visualize the lesions of esophagus and stomach and biopsy to obtain pathological basis.