The symptoms of small pulmonary nodules are as follows: 1. Most small pulmonary nodules, without particularly obvious symptoms, are only found during physical examination or hospitalization for other diseases; 2. Some patients have atypical symptoms, manifesting as mild chest tightness, chest pain or cough, and such symptoms are not strongly associated with pulmonary nodules. When the pulmonary nodules are larger and cause bronchial obstruction or pleural effusion, symptoms such as irritating dry cough, hoarseness, shortness of breath and chest tightness will appear. The symptoms of localized chest tightness and chest pain in some patients after the discovery of pulmonary nodules are mainly related to psychological factors. Patients who are long-term smokers, older than 45 years old, and have a history of extra-pulmonary tumors or a family history of tumors are recommended to have annual lung CT physical examinations.