Lung CT 2 years ago is normal 2 years later there is a 10mm nodule, if it belongs to benign nodules, the condition is generally not serious, but the exact severity depends on the progress of the disease; if it is malignant nodules, it is more serious. 1. Benign nodules: lung nodules may be pneumonia, tuberculosis, some patients may be lung cysts, pulmonary fibroma, etc. These benign nodules are not serious in themselves, and can be cured by timely treatment; however, if the condition is neglected, it may cause complications. 2. Malignant nodules: for example, primary lung cancer and secondary lung cancer, which are more serious and more dangerous to patients’ lives. However, through timely treatment at early stage, the survival period can usually be prolonged. If the presence of lung nodules is found again through CT, the patient should consult the doctor in time and analyze the nature of nodules through pathological biopsy.