Many people are frightened to find a “lung nodule” during a physical exam or hospitalization. Here are some questions about pulmonary nodules. Any lesion smaller than 3 cm on a chest CT can be called a pulmonary nodule. Pulmonary nodules can be formed by a variety of causes (e.g., lung infection, chronic inflammation, benign growths, malignancy). If a pulmonary nodule is found, the focus is on the determination of whether it is a malignant tumor. For comparatively larger than 8 mm, ground glass-like round nodules, especially in combination with some pleural traction signs/concavity, short burr-like, early tumor is more likely. The decision to surgically remove the nodule and the type of surgery depends on a variety of factors including the patient’s age, cardiopulmonary function, and the location of the nodule, and requires consultation with the thoracic surgeon. Most of the lung nodules may require long-term follow-up. The follow-up interval is usually based on the tendency of the nodule nature: 2-6 months for nodules suspected to be early-stage tumors, and more clearly for small lung nodules with thin-layer CT, which can be extended if there is no significant change for several years. However, there are some tumors that grow very slowly. Some patients have no change after 7 or 8 years of follow-up, and then they gradually become larger, and after surgery, they are indeed malignant tumors. If it is indeed a tumor, there is less need to worry about significant changes over a period of months. On the contrary, rapid changes over a short period of time are not characteristic of primary tumors of the lung in general. The follow-up period may be longer for lesions that tend to be chronic inflammatory or benign. Therefore, it is not scary to find lung nodules and follow the advice of respiratory medicine, thoracic surgery and oncology doctors in regular hospitals for follow-up and observation or surgical treatment to improve the quality of life.