Lung cancer is the most common primary malignant tumor of the lung. Most lung cancers originate from the bronchial mucosa epithelium, so it is also called bronchial lung cancer. In recent 50 years, the incidence rate and death rate of lung cancer have been increasing rapidly all over the world, especially in industrialized countries, and lung cancer has taken the first place among male patients who died of cancer. Signs of lung cancer 1.Limited croup is a limited croup, which mostly appears in the inspiratory stage and does not disappear after coughing. 2.Heartness of voice It appears when lymph node metastasis compresses or invades the recurrent laryngeal nerve. 3.Superior vena cava syndrome Tumor compression or invasion of superior vena cava, venous return obstruction, resulting in edema of head, face, neck and upper limbs, varicose veins and edema of upper chest, accompanied by dizziness, chest tightness and shortness of breath. 4.Horner’s syndrome When apical lung cancer compresses or invades the cervical sympathetic ganglion, the sunken eye on the affected side, ptosis, narrow pupil, narrow eye fissure, increased skin temperature of upper chest on the affected side and no sweating will appear. 5.Shoulder and arm pain When apical lung cancer compresses or invades the brachial plexus nerve, radiating burning pain of the shoulder and upper limb on the affected side will appear. 6.Phrenic nerve paralysis When the phrenic nerve is invaded, shortness of breath and chest tightness will appear. 7.Difficulty in swallowing It is caused by the enlargement of mediastinal lymph nodes compressing the esophagus, and the compression of trachea may cause difficulty in breathing. 8.pericardial invasion When the pericardium is invaded, pericardial effusion, shortness of breath, cardiac arrhythmia, cardiac insufficiency, etc. may occur. 9.Pleural metastasis can be seen as chest pain, cancerous pleural fluid, etc. 10.Lung cancer metastasis The common sites of lung cancer metastasis are bone, liver, brain, kidney, adrenal gland, subcutaneous tissue, etc. In addition, internal metastasis of lung cancer is also more common. The clinical symptoms and signs vary according to the metastatic sites. 11.Extrapulmonary signs Commonly include joint pain or hypertrophy of limbs, pestle finger, polyneuritis, myasthenia gravis, Cushing’s disease, gynecomastia, hypercalcemia, mental abnormalities, etc. The early symptoms of cancer are not obvious and are usually found to be at an advanced stage. We would like to remind you that if you find any physical abnormality, you should go to the regular hospital for diagnosis and examination in time.