Q1: Can lung cancer be predicted? A1: Yes, Mayo Clinic’s lung cancer prediction model, like other lung cancer prediction models, uses the patient’s clinical risk factors and nodal characteristics to predict the likelihood of lung cancer. Clinically, some physicians (especially pulmonologists or respiratory physicians) do use the formula to assist their own judgment of the benignity of SPN through consultation and radiology CT reports, but of course, it can only be used as a reference for individual patients, and if they rely on the formula, they will definitely make mistakes. The predictive approach is as follows: clinical risk factors such as older age, current or past history of smoking and history of extrathoracic malignancy for more than 5 years prior to nodal detection are important predictors of malignancy; MDCT examination showing nodal size, burr and nodal location in the upper lobe of the lung are all associated with malignancy. In addition PET may also enhance the predictive model. In brief, the patient’s age, whether he/she has a history of smoking, whether the history of extrathoracic malignancy is more than 5 years before nodule detection, the size of the nodule, the presence of burr and whether the nodule is located in the upper lobe of the lung are each substituted into a natural logarithm model to calculate the predictive value to predict the benignity of SPN. Q2: What should I do if a solid SPN is found? A2: Solid nodules that have not changed for more than 2 years or nodules with benign calcification patterns do not require further examination. For SPNs less than 4 mm, the chance of lung cancer in patients without a history of cancer is less than 1%, so further evaluation is generally considered unnecessary. The American Fleischner Society recommends the following follow-up protocol for patients with solid SPN: for SPN ≤ 4 mm in diameter, no follow-up is required for low-risk patients and follow-up at 12 months for high-risk patients; for SPN 5-6 mm in diameter, follow-up at 12 months for low-risk patients and follow-up at 6-12 months and 18-24 months for high-risk patients; for SPN 5-6 mm in diameter, follow-up at 6-12 months and 18-24 months for low-risk patients; and for SPN 5-6 mm in diameter, follow-up at 6-12 months and 18-24 months for low-risk patients. ～For SPN diameters of 5-6 mm, low-risk patients were followed up at 6-12 months and 18-24 months, and high-risk patients were followed up at 3-6 months, 9-12 months, and 24 months; for SPN diameters >8 mm, both low-risk and high-risk patients were followed up at 3, 9, and 24 months, and enhanced CT, PET-CT, and puncture biopsy were considered. [Low-risk patients are considered low-risk when there is little or no history of smoking and other risk factors; high-risk patients are considered high-risk when there is a history of smoking or other exposures or other factors. Q3: Is there any further attention to be paid to solid SPN with a diameter >8 mm? A3: First of all, for solid SPN >8 mm in diameter, a pre-experimental assessment of the possibility of malignancy should be done. When the assessment of SPN is low (<5%), low-dose MDCT follow-up can be performed at 3, 6, 12 and 24 months. When the assessment of SPN is moderate (5% to 60%), PET-CT or CT-enhanced examination is feasible. If the result is negative, case follow-up CT or puncture/surgical excision can be performed to obtain tissue for pathological examination; if the result is positive, direct puncture/surgical excision can be performed to obtain tissue for pathological examination. When the assessment of SPN is high (>60%), direct puncture/surgical excision for pathological examination is also performed. Q4: What is the best way to manage GGO nodules ≤5 mm in diameter? A4: The American Fleischner Society recommends no CT follow-up for GGO nodules ≤5 mm in diameter, but 1 mm layer thickness CT should be used to confirm that the nodule is indeed a pure GGO nodule. Q5: What is the best follow-up for GGO nodes >5 mm in diameter? A5: The American Fleischner Society recommends CT follow-up after 3 months for GGO nodules >5 mm in diameter to determine if the nodule is still present, followed by annual CT review for at least 3 years. The current routine FDG PET examination is of limited value in this area, has the potential to be misleading and is not recommended at this time. However, research is ongoing in this area of FDG PET-CT, and it is possible that the diagnostic value will be improved in the near future due to refinement of the examination technique, which we are looking forward to. Q6: What is the best way to manage partially solid SPN (i.e. mGGO) nodules? A6: The American Fleischner Society recommends CT follow-up after 3 months for partially solid SPN, or mGGO nodules to determine if the nodule is still present. If the nodule persists and the solid portion is <5 mm in diameter, CT review should be performed annually for at least 3 years; if the nodule persists and the solid portion is ≥5 mm in diameter, puncture biopsy or surgical resection should be performed.