Chest distension is considered to be chest tightness. Lung tumors can lead to the symptom of chest tightness, but there are many reasons for chest tightness, which are not necessarily caused by lung tumors. 1. Respiratory system diseases: such as lung tumor, tracheal stenosis, pulmonary atelectasis, etc., which can lead to chest tightness and discomfort in the chest. 2. Digestive system diseases: such as gastritis, gastric dyskinesia, etc., which can cause bloating and chest tightness in the upper abdomen. 3. Heart diseases: such as coronary heart disease, endocarditis, etc., also sometimes manifest chest tightness, shortness of breath, chest pain, etc.. 4. Menopausal syndrome: some menopausal women may also experience chest tightness and bloating. The symptoms of chest distension alone can not accurately determine the cause, but also need to be combined with the characteristics of the medical history, other test results to make an accurate judgment, it is recommended to clarify the cause of the disease under the guidance of a doctor.