Thin-walled cystic cavities in the lungs are not necessarily lung cancer; most of them may be lung cysts, pulmonary pustules, tuberculosis, fungal infections of the lungs, and lung parasites. Thin-walled cystic cavities in the lungs are bubble-like cavities that appear on imaging films, encased by surrounding cyst-like tissue. Most people are found after a physical examination, may not have symptoms, the probability is that the lung cysts, pulmonary macroglossia, there is no special discomfort, do not need to deal with, regular review can be. Some people have cough and other discomforts, they may have special type of infection, the pathogenic microorganisms in the infected foci will form cavities after discharging from the lung tissues through coughing, most common is cavitary tuberculosis, and a few of them may be special infections such as Pneumocystis carinii pneumonia. There is also a type of cystic lung cancer that may present with thin-walled cystic cavities in the lungs, but it is rare. If abnormalities are detected during physical examination, it is recommended to go to a specialized institution as soon as possible for treatment.