For 5mm lung nodules, it is usually not too late to have a review once every six months, but it is not possible to generalize. According to the nature of the lung nodule, morphology, medical history and other factors to determine the comprehensive, specific to the guidance of the specialist. 1. Lung nodules can be benign or malignant, and the probability of malignancy of lung nodules less than 5mm is less than 5%. Generally speaking, the probability of a 5㎜ nodule developing into lung cancer in a short period of time is relatively small. Regular follow-up is recommended, and the follow-up period is usually 6-12 months, based on the advice of a specialist. 2. If there are older age, long-term smoking history, previous history of tumor, larger diameter of the nodule, burr around the nodule, or the nodule is located in the upper lobe, the possibility of malignant nodule is higher, and then it is necessary to go to a professional medical institution in time for diagnosis and treatment. If you find a lung nodule, please go to the hospital in time and make a treatment plan under the guidance of a specialist.