As we know, the typical symptoms of lung cancer are cough, blood in sputum, chest pain, shortness of breath and other lung manifestations; however, according to statistics, about half of lung cancer patients show symptoms outside the lungs at the beginning, and they often appear before the lung symptoms, and patients often ignore some of the extra-pulmonary symptoms and cause delay in diagnosis. Therefore, we need to be alert and pay attention to these signs, which will help in early diagnosis and early treatment. Next, let’s take a look at the main extra-pulmonary symptoms of lung cancer: 1. Pay attention to the extra-pulmonary intra-thoracic symptoms. As the tumor invades the pleura: chest wall and mediastinal organs and intra-thoracic nerves, it can cause a series of chest symptoms. Tumor invasion of pleura can cause breathing pain and pleural effusion (i.e. pleural fluid), and bloody pleural fluid indicates bad prognosis. If malignant tumor cells are found in the pleural fluid, the chance of surgery will be lost. The involvement of tumor in mediastinum is mostly caused by mediastinal lymph node metastasis, and few of them are direct invasion. In 5% of patients, tumor compression of superior vena cava causes swelling of upper limbs and above shoulder, venous anger, headache and difficulty in breathing, which means it is in advanced stage. Tumor compression on esophagus can cause difficulty in swallowing, and invasion of laryngeal nerve can cause hoarseness. 2.Extra-thoracic metastasis symptoms of lung cancer patients. Lung cancer often metastasizes along lymphatic vessels and blood vessels, and metastases to lymph nodes in the neck, liver, adrenal gland, bone, kidney and brain are common. Nearly 15% of patients have metastases as the earliest symptom, and hematogenous metastases are most common in adenocarcinoma and small cell lung cancer. 3. Extrathoracic non-metastatic symptoms in lung cancer patients. Extrathoracic non-metastatic symptoms can appear in only 2% of patients, but the symptoms are complex, involving more systems and the etiology mechanism is unknown. Scleroderma, etc. 4. Systemic symptoms of lung cancer patients. Patients with lung cancer will also have common symptoms of other tumors, such as anorexia, emaciation, weakness, etc., and finally develop into cachexia, etc. 5. Male breast hypertrophy: About 10%-20% of male lung cancer patients have breast hypertrophy, some unilateral hypertrophy, but most of them are bilateral hypertrophy, and this symptom appears about one year earlier than lung symptoms such as cough, blood in sputum, chest pain and shortness of breath. This is because certain lung cancer cells can secrete chorionic gonadotropin, a hormone that can cause hyperplasia of breast tissue and make the breast hypertrophy.