Most lung nodules are benign in clinical practice, and it takes about half a year or even longer for them to turn into malignant tumors. Clinically, it is impossible to distinguish benign from malignant lung nodules in the early stage, and regular chest CT examination is needed to clarify their growth rate and size. The nature of the nodule should be clarified by puncture, and it can be removed surgically, which is curable for early stage lung cancer. For late stage lung nodules, the rate of enlargement will increase significantly and will grow to the size of a ping pong ball or larger in about 3-5 years, depending on the individual’s physical condition. If the patient is young and has a strong metabolism, then the growth rate of lung cancer will be faster. If the patient is old and has a slow metabolism, then the growth of lung cancer lesions will be slow.