Air bubbles on the lungs are generally referred to as pulmonary blisters in medical terms, which are not usually cancerous. Pulmonary blisters are usually secondary to lung diseases such as emphysema and asthma, but some may also be caused by idiopathic or congenital genetic abnormalities. Usually, pulmonary blisters arise when the pressure in the alveolar cavity is increased for various reasons and the walls of small alveoli rupture and the ruptured alveoli fuse with each other to form relatively large air sacs. Lung cancers often manifest as irregularly shaped masses or eccentric cavities in the lungs. Such cavities are mainly caused by excessive tumor growth and lack of blood supply to the central part of the tumor. In most cases, imaging tests are able to distinguish between pulmonary maculopathy and pulmonary cancer cavities. Pulmonary blister is a benign disease and usually not cancerous, so patients do not need to worry too much that the air bubbles on the lung will become cancerous. Patients should pay attention to rest, quit smoking and alcohol in daily life, and avoid staying up late, holding breath, coughing violently, lifting heavy objects, catching cold, etc. to avoid rupture of pulmonary blisters, which may lead to breathing difficulties.