For lung nodules, they can be graded according to pni-rads, which can be categorized into six grades; Grade I, no nodules detected. Grade II, benign nodule. Grade III, undetermined nodules. Grade 4, suspected malignant nodule, which is further divided into three grades, A, B, and C. 4A is a relatively high risk of malignancy, 4B is a direct suspicion of carcinoma in situ, or a high likelihood of microscopic invasive carcinoma, and 4C is a very high likelihood of malignancy. Grade 5, after CT screening strongly suggests malignant nodules. Grade 6, the histology has confirmed that it is a malignant nodule. From grade 1 to grade 6, the likelihood of malignancy gradually increases, and the treatment is different for different degrees of malignancy: for grade 1, routine screening is sufficient. In the second level, if the nodule is determined to be benign, it can be left alone, but there are other parts that need to be followed up and should be followed up regularly according to the schedule set by the doctor. At the third level, the doctor will set up different follow-up schedules according to the size of the nodules. In the fourth level, the doctor should make different checkups and follow-up plans according to A, B, and C. In the case of Grade V, further tests are routinely performed to clarify the diagnosis to determine the next step in treatment. And in grade 6, it is a confirmed malignant tumor, so the next step of treatment should be actively pursued.