I. What are the functions of the lungs? Located in the chest cavity, the lungs are important organs of the respiratory tract and are divided into the left and right lungs. Its function is to inhale oxygen and expel carbon dioxide to maintain the normal metabolism of human body. What is lung cancer? Lung cancer is the malignant transformation of bronchial epithelial cells or alveolar epithelial cells of lung tissues, which further grows and expands to form a cancerous tumor, and can spread to the surrounding and even the whole body. What are the main factors of lung cancer? Smoking. Atmospheric pollution: such as automobile exhaust, factory exhaust. 3, Living environment pollution: such as the use of irritating decorative materials, oil smoke, carbon monoxide produced by incomplete combustion of coal. What are the common early symptoms of lung cancer? 1. Cough: mostly paroxysmal, irritating dry cough. Hemoptysis: mostly blood in sputum or blood sputum. Chest and back pain, chest tightness. What are the common examination methods for diagnosing lung cancer? Chest X-ray examination. Sputum cancer cell examination. Precautions for retaining sputum: a. After gargling on an empty stomach in the early morning, cough repeatedly and continuously, and then cluck out the deep sputum with force. b. The sputum must be coughed out from the lungs and trachea, and the saliva and nasal mucus should not be mixed into the sputum for examination. c. Sputum should be blood sputum, gray-white sputum or transparent mucus sputum. d. 1-2 mouthfuls of sputum for each test. e. Sputum should be sent for testing for three consecutive days. f. Sputum must be sent for examination within 4 hours. 3.Fiberoptic bronchoscopy. Precautions: a. Signed by family members. b. Fasting and water fasting for 4 hours to prevent intraoperative vomiting and aspiration. c. Preoperative injection half an hour before the operation. d. Blood in the sputum after the examination will disappear quickly and automatically, which is a normal phenomenon. e. Fasting and water fasting for 2 hours after the examination. f. Chest CT scan. g. Finding cancer cells in chest water. What should be paid attention to the diet of lung cancer patients? High fat, moldy food, cured ham and smoked food, pesticide-polluted food containing carcinogenic substances should be avoided. It is better to eat “three high and one low” diet with high protein, high vitamin, high calorie and low fat, especially eating more fresh vegetables and fruits. What are the common methods of lung cancer treatment? Lung cancer treatment is a multidisciplinary comprehensive treatment, commonly used methods include surgery, radiotherapy, chemotherapy, targeted therapy, traditional Chinese medicine treatment, immunotherapy, etc., among which surgery is the most important treatment means.