People with large pulmonary alveoli do not become lung cancer; there is no necessary connection between the two. A pulmonary alveolus is a condition of increased alveolar pressure in which the walls of the alveoli rupture and fuse into an air-containing cystic cavity, which may cause a pneumothorax. Lung cancer, on the other hand, is a malignant tumor that occurs in the lungs. In adolescent patients with pulmonary alveoli, often caused by congenital dysplasia of the lungs, this condition is usually not cancerous. Middle-aged and elderly patients with large alveoli are at risk of cancer if they have a combined lung infection and suffer from long-term inflammatory stimuli, and the cancer rate is usually less than 20%. It is recommended that patients with pulmonary alveoli and other chronic diseases should consult a doctor in time to clarify the cause of the disease, and undergo appropriate examination and treatment if necessary.