Introduction to lung cancer

Disease Name: Introduction to Lung Cancer: Lung cancer occurs in the bronchial mucosa epithelium, also known as bronchial carcinoma. In the past 50 years, the incidence of lung cancer has been reported to increase significantly in many countries. Among male cancer patients, lung cancer has ranked first, and the incidence rate in women has also increased rapidly, accounting for the second or third place of common malignant tumors in women. The etiology of lung cancer is still not fully clear. A large amount of data indicates that long-term large amount of cigarette smoking is an important cause of lung cancer. For more than 40 cigarettes per day for many years, the incidence of lung squamous cell carcinoma and undifferentiated carcinoma is 4 to 10 times higher than that of non-smokers. The incidence of lung cancer in urban residents is higher than in rural areas, which may be related to air pollution and carcinogens in smoke. Therefore, it should promote non-smoking and strengthen urban environmental sanitation. Causes: (1) Causes of the disease The risk factors for lung cancer are: 1. Smoking In 1922, Hampeln found that continuous smoking and inhalation of dust can stimulate the bronchial epithelium to induce cancer. In 1924, Moller applied tar to the back of the rabbit and found that the incidence of lung cancer increased slightly. At present, smoking is considered to be the most basic risk factor for lung cancer. There are more than 3,000 kinds of chemicals in tobacco, and multi-chain aromatic hydrocarbon compounds (such as benzopyrene) have strong carcinogenic activity. Certain special enzymes that act on human tissues (especially lung tissue) produce mutations in cellular molecular structures (such as DNA) that may have mutations in K-ras. 2. Occupational and environmental exposures It is estimated that up to 15% of lung cancer patients have a history of environmental and occupational exposure, and there is sufficient evidence to confirm that the following nine industrial components increase the incidence of lung cancer: by-products of aluminum products, arsenic, asbestos, bis-chloromethyl ether, Chromium compound, coke oven, mustard gas, nickel-containing impurities, vinyl chloride. Long-term exposure to sputum, cadmium, silicon, formalin and other substances will also increase the incidence of lung cancer. In addition, air pollution, especially industrial waste gas, is a high risk factor for lung cancer. 3. Radiation uranium and fluorspar miners are exposed to inert gas helium, decaying uranium by-products, etc., which is significantly higher than other people's lung cancer, but people with ionizing radiation do not increase lung cancer. 4. In patients with chronic lung infections such as tuberculosis and bronchiectasis, the bronchial epithelium may become squamous in the process of chronic infection, eventually causing cancer, but such cases are rare. 5. Intrinsic factors family, genetic and congenital factors as well as decreased immune function, metabolic, endocrine dysfunction, etc. may also be a high risk factor for lung cancer. 6. The incidence of lung cancer in developed countries is high, the city is higher than the rural areas, and the factory and mining areas are higher than the residential areas. The main reason is due to the industrial and transportation developed areas, oil, coal and internal combustion engines, and the burning of asphalt roads. It is related to the harmful substances such as benzopyrene carcinogenic hydrocarbons polluting the atmosphere. The survey materials indicated that the incidence of lung cancer was also increased in areas with high concentrations of benzopyrene in the atmosphere. Air pollution and cigarette smoking may promote each other's incidence of lung cancer and play a synergistic role. (B) the pathogenesis of lung cancer metastasis has the following four ways: 1. Direct spread of cancer continues to grow, can block the bronchial lumen, while also expanding into the extrapulmonary lung tissue. Tumors near the periphery of the lung can invade the pleura and chest wall, and tumors with a central or near mediastinum can invade the pleura and chest wall, and tumors with a central or near mediastinum can invade other organs. A huge tumor can cause central ischemic necrosis and form a cancerous cavity. 2. Hematogenous metastasis is a late manifestation of lung cancer. Cancer cells can be transferred to any part of the body after returning to the left heart with the pulmonary veins. The common metastatic sites are liver, brain, lung, bone system, adrenal gland, kidney and pancreas. 3. In the case of disseminated alveolar cell carcinoma in the bronchus, the cancer cells on the bronchioles and alveolar walls are easily detached; the cancer cells can diffuse through the bronchial tubes into adjacent lung tissues to form new cancerous foci. 4. Lymphatic drainage of the lymphatic metastasis has a certain regularity. The right upper lobe flows to the right hilar and right upper mediastinal lymph nodes. The middle lobe of the right lung flows to the lymph nodes of the middle and lower lobe summary area, the subcarinal and the right upper mediastinal lymph nodes. The right lower lobe leads to the middle and lower lobe summary area, the subtotal ligament, the lower lung ligament and the right upper mediastinal lymph node. The left upper lobe leads to the aortic arch (Bottallo) lymph node and the left anterior superior mediastinal lymph node. The left lower lobe lymph flow is in the upper and lower lobe summary area, under the bulge and across the mediastinum to the right superior mediastinal lymph node. For example, lymph node metastasis (N state) of lung cancer can be shown using the lymph node legend of Maoshof (Fig. 1). Symptoms: Early asymptomatic, almost 2/3 of lung cancer patients are advanced at the time of presentation (stage III or IV), 95% of patients may have clinical findings, primary tumors, metastases, systemic symptoms or tumors Symptoms can be the patient's first diagnosis. The primary symptoms caused by primary tumors accounted for 27%. Symptoms were related to the location of the primary tumor. Central lung cancer was characterized by irritating dry cough, belching, recurrent pneumonia, hemoptysis or asthma, recurrent laryngeal nerve, and phrenic nerve compression. Symptoms or superior vena cava compression syndrome. Peripheral tumors are more common symptoms such as chest pain, hernia or pleural effusion. Large peripheral lesions, central necrosis, and voids eventually show similar lung abscesses, and the common symptoms of primary lung cancer are grouped. Distal metastases account for 32% of the first symptoms, and common distant metastases are: lymph nodes, adrenal glands, liver, bone, lung, brain and chest wall, which produce some corresponding symptoms, indicating that lung cancer has reached advanced stage, such as: proximal mediastinum The tumor can invade the phrenic nerve, causing ipsilateral diaphragmatic paralysis, showing increased diaphragmatic position and abnormal respiratory movement under fluoroscopy; invading the ipsilateral recurrent laryngeal nerve, causing hoarseness, ipsilateral vocal cord paralysis and fixation in the median position; Vena cava, causing edema of the head and face and upper limbs, venous engorgement; invasion of the pleura. Causes a large amount of bloody effusion in the pleural cavity, aggravating the symptoms of shortness of breath, or directly invading the chest wall, causing severe chest pain; the upper tip of the lung cancer is at the entrance to the thoracic cavity, also known as the upper sulcus cancer, which can invade and compress the brachial plexus and neck. The sympathetic ganglia and the subclavian arteries and veins produce a series of special, cervical sympathetic ganglia and subclavian arteries and veins, which produce a series of unique symptoms, such as numbness and pain in the lateral upper limbs, which gradually increase the difficulty of tolerance; muscle and skin present Atrophic changes, upper extremity venous engorgement and edema; and ipsilateral ptosis, pupil dilation, eyeball invagination, facial sweatless neck and other cervical sympathetic syndrome. 10% to 20% of lung cancer patients with tumor-associated syndrome, the most common accompanying such symptoms are small cell lung cancer and squamous cell carcinoma, common tumor associated syndrome is: pulmonary osteoarthrosis syndrome (skull finger , bone and joint swelling and pain, periosteal hyperplasia, etc., SIADH (antidiuretic hormone secretion syndrome), hypercalcemia, etc., as well as Cushing's syndrome, myasthenia gravis or male mammary gland enlargement, about 16% The patient is accompanied by neuromuscular symptoms. Some patients have skin diseases such as scleroderma and acanthosis. The clinical manifestations of lung cancer are closely related to the location and size of the cancer, whether it is oppressed, invasion of adjacent organs, and the presence or absence of metastasis. Cancer grows in larger bronchi, often with irritating cough. Increased cancer affects bronchial drainage, and there may be purulent sputum secondary to pulmonary infection. Another common symptom is blood stasis, usually with blood spots, bloodshot or intermittent hemoptysis in some sputum; some patients have important reference value even if they have blood or sputum once or twice. Some patients may have chest suffocation, shortness of breath, fever and chest pain due to large bronchial obstruction caused by the tumor. When advanced lung cancer oppresses adjacent organs, tissues, or distant metastases, it can produce: 1 oppression or invasion of the phrenic nerve, causing ipsilateral diaphragmatic paralysis. 2 oppression or invasion of the recurrent laryngeal nerve, causing hoarseness in the vocal cords. 3 compression of the superior vena cava caused facial, neck, upper limb and upper chest vein engorgement, subcutaneous tissue edema, upper limb venous pressure increased. 4 invasion of the pleura, can cause pleural effusion, mostly bloody. 5 cancer invades the mediastinum and oppresses the esophagus, which can cause difficulty in swallowing. 6 Upper lobe top lung cancer, also known as Pancoast tumor or superior sulcus tumor, can invade and compress organs or tissues located in the upper thorax, such as the first rib, superior supraclavicular artery and vein, brachial plexus, cervical sympathetic nerve, etc. Chest pain, jugular vein or upper extremity venous engorgement, edema, arm pain and upper limb dyskinesia, ipsilateral upper eyelid ptosis, pupil dilation, eyeball invagination, facial sweatless neck and other cervical sympathetic syndrome. A small number of lung cancers, due to the secretion of endocrine substances in cancer, clinically present non-metastatic systemic symptoms: such as bone and joint syndrome (skull, joint pain, periosteal hyperplasia, etc.), Cushing syndrome, myasthenia gravis, male breast enlargement Extrapulmonary symptoms such as multiple muscle neuralgia. These symptoms may disappear after removal of lung cancer. Diagnosis: Only early diagnosis and early treatment can achieve better curative effect. Therefore, it is necessary to publicize the anti-cancer knowledge widely. For adults over 40 years of age, a chest X-ray survey should be performed once every six months. For those who have had suspicious symptoms such as chronic cough, blood stasis, and lung shadow, a series of detailed examinations should be performed to confirm the diagnosis. For nodules ≤5mm found in the census, it should be reviewed every 3 months; nodules of 6~10mm size should be percutaneous biopsy. If biopsy is not available, CT should be reviewed every 3 months; >1cm knot Section, should be biopsy. Lung cancer is currently using the clinical phase of the TNM system published by the International Union Against Cancer in 1997, and is only suitable for non-small cell lung cancer. Small-cell lung cancer often uses a two-stage system: limited and extensive. The limitation is defined as: the lesion is confined to one side of the chest, with or without ipsilateral mediastinum or supraclavicular lymph node metastasis. It accounts for only 26% of small cell lung cancer. The broad type is defined as the extent to which the lesion exceeds the defined range. Corresponding to one or more TNM indicators, there are four stages of tumor staging, the prognosis of stage I is the best, and the stage IV is the worst. Identification of typical lung cancer is easy to identify, but in some cases, lung cancer is easily confused with: Read more...