The common symptoms of lung metastasis include dyspnea, hemoptysis, chest pain and so on. 1. Difficulty in breathing: when the tumor from other parts metastasizes to the lungs and develops lung metastasis, the tumor cells will easily damage the alveoli, meanwhile, the tumor may block the airway, affecting the gas exchange of lungs, and the patient will have the symptom of dyspnea. 2. hemoptysis: the tumor invades the central airway, which may cause cough, blood in sputum, hemoptysis and so on. 3. Chest pain: when the volume of lung metastases increases, it will easily involve the pain nerve and cause chest pain. If the tumor cells metastasize or spread to the pleura, due to the large number of nerve endings in the pleura, the tumor can easily stimulate the nerve endings and cause chest pain. If patients have the above symptoms, it is recommended to go to professional hospitals as soon as possible to avoid delaying the condition.