If lung nodules are found on physical examination, further review of CT of both lungs and lung puncture biopsy if necessary are recommended. 1. Review of CT of both lungs: Lung nodules are solid or sub-solid shadows with a diameter of less than 3mm. Most of the lung nodules seen on CT scan are caused by old infections, scar tissue or other reasons. Therefore, if a physical examination reveals lung nodules, a repeat CT scan of both lungs is needed, and the time between reviews may vary from a few months to a year. 2. Lung puncture biopsy: If repeated scans show that the nodule has grown or there are symptoms (chest pain, hemoptysis, cough, weight loss), it is feasible to puncture the lung to do pathological examination to clarify the nature of the nodule. If the physical examination reveals lung nodules, it is recommended to decide the time and items to be reviewed under the guidance of the clinician.