Lung cystic lucencies are not necessarily cancerous, but if they are caused by cancer, they may be accompanied by lobar signs, burr signs and other signs. In addition, cystic lucency may be caused by benign lung lesions, inflammation of the lungs, and other conditions. Cancer in the lungs may appear as cystic translucent shadow on CT or MRI, which is usually considered to be caused by bronchopulmonary squamous carcinoma. In addition, patients with bronchopulmonary squamous carcinoma may have lobar sign, burr sign, vacuolar sign, hilar mass, eccentric cavity and other signs in CT examination. In addition, patients with cystic translucent shadow on lung CT or MRI are also considered to be caused by benign lesions such as lung cyst, lung abscess, emphysema, as well as diseases such as pneumonia, tuberculosis, and so on. It is recommended that patients who have cystic translucent shadows on lung imaging need to consult a doctor in time, and the doctor will judge whether it is caused by cancer according to the examination results and the patient’s physical condition. In addition, the doctor will choose the appropriate treatment according to the cause of the cystic lucency of the lungs.