A soft tissue mass in the left lung may be a benign tumor or a malignant tumor. 1. Benign tumors: most benign lesions are soft tissue masses in the lungs, which require CT examination. If there is no obvious clinical manifestations, there will be no cough, sputum, hemoptysis and other symptoms, the possibility of benign is very high, the need for early surgery. 2. Malignant tumors: patients with malignant tumors will have symptoms such as lung pain, cough, hemoptysis, etc., which can cause pulmonary edema in severe cases. It is recommended to go to thoracic surgery clinic for chest CT and bronchoscopy in time to clarify the specific condition. According to the condition, targeted therapy, immunotherapy, chemotherapy and other treatments can be chosen to improve the survival of lung cancer patients. Patients with soft tissue mass in the left lung are recommended to go to the hospital for timely examination and standardized treatment under the guidance of doctors. Normally, they should pay attention to strengthening nutrition, eating more fresh fruits and vegetables, drinking more water, not smoking and so on.