1. Why have there been a lot of pulmonary appearances in recent years? In recent years a significant number of small pulmonary nodules have been detected in medical examinations. According to statistics about 20% or so of the population CT will detect small lung nodules, including a significant proportion of ground glass nodules. The reason for this is mainly 2 points 1) the popularity of physical examination, especially the widespread use of chest CT in physical examination. In the past, it was extremely difficult to diagnose non-small nodules on chest radiographs, and with the spread of CT, nodules as small as 2 mm have been detected. 2) Increasing morbidity. It is related to environmental pollution, smoking, etc. 2. What exactly is a small lung nodule? Non-small nodules mainly include benign infectious lesions, tuberculosis, fungus, malignant neoplasm, etc. Pre-infiltrative neoplastic lesions include atypical adenomatous hyperplasia, carcinoma in situ and other such post-surgical survival close to benign lesions. Malignant neoplastic lesions include mainly adenocarcinoma, small cell lung cancer, metastatic cancer, etc. 3.How to identify whether a non-small nodule is benign or malignant? It is a difficult problem in medicine, but there are certain rules to follow. (1) Size: if the nodule is less than 5mm, malignancy is less than 5%. 5-10mm6-28%. 10mm or more single lung nodules may be more than 50% malignant. (2) morphology, density, margin, etc.: for example, high density and uniform margin smooth, mostly benign lesions, surrounded by burrs the vast majority are malignant. Ground glass nodules – the possibility of malignancy is 18% The possibility of malignancy of mixed ground glass nodules is 63%. (3) Those with risk factors. Including smoking, smoking index (daily only x number of years) 400 or more. 55 years or more, history of chronic lung disease, family history. Occupational exposure, etc. 4.What should I do if I find a small lung nodule? The first step is to seek professional medical consultation and consultation. It is recommended to follow up CT in 12 months for those below 5m, 3-6 months for those 6-8mm, and review after regular anti-inflammation for those with possible inflammation. The follow-up interval can be lengthened if there is no change. For those with 3-5 years, surgery may be considered if there are risk factors or enlargement during the follow-up period. For small pulmonary nodules, minimally invasive thoracic surgery is currently very suitable. These include three-hole and single-hole thoracoscopic surgery, which is less risky, less traumatic and quicker to recover, with fewer sequelae. Not to the extent that people will have doubts, will not delay the treatment. Lung nodules, especially ground glass nodules, develop slowly. Lymphatic and distant metastases do not occur in the short term. The multiplication period of ground glass nodules is long, up to 3 years for pure ground glass. Inert tumors predominate, and survival after surgery is close to 100%. 5.How to prevent small nodules? There is no specific means of prevention, keep good living habits, more exercise, no smoking, keep cheerful mood, etc. Most of the tumors are caused by the imbalance of autoimmunity, and the good state of autoimmunity is the basis of preventing tumors. The increase of female patients is related to cooking habits, reduce the production of fried food and keep the kitchen well ventilated. Regular medical checkups are especially important. Through scientific means, there is no need to panic even if nodules are detected in the lungs. Most of them are benign lesions. Even small malignant nodular lesions can be treated satisfactorily.