1. Smoking
At present, smoking is considered as the most important risk factor for lung cancer. There are more than 3,000 chemical substances in tobacco, among which polycyclic aromatic hydrocarbons (such as benzopyrene) and nitrosamines have strong carcinogenic activity. Polycyclic aromatic hydrocarbons and nitrosamines can cause DNA damage of bronchial epithelial cells through various mechanisms, activate oncogenes (such as Ras genes) and inactivate tumor suppressor genes (such as p53 and FHIT genes), thus causing cell transformation and eventually canceration.
2. Occupational and environmental contact
Lung cancer is the most important occupational cancer. It is estimated that about 10% of lung cancer patients have a history of environmental and occupational exposure. It has been proved that the following nine occupational carcinogens increase the incidence of lung cancer: by-products of aluminum products, arsenic, asbestos, dichloroethane, chromium compounds, coke ovens, mustard gas, impurities containing nickel and vinyl chloride. Long-term exposure to beryllium, cadmium, silicon, formalin and other substances will also increase the incidence of lung cancer, and air pollution, especially industrial waste gas, will cause lung cancer.
3. Ionizing radiation
The lung is an organ sensitive to radiation. The preliminary evidence of lung cancer caused by ionizing radiation comes from the data of Schneeberg-joakimov mine, where the concentration of radon and its daughters in the air is high, and most of them are induced by bronchial small cell carcinoma. It has been reported in the United States that 70% ~ 80% of miners who mine radioactive ore died of radiation-induced occupational lung cancer, mainly squamous cell carcinoma. The time from first contact to onset was 10 ~ 45 years, with an average time of 25 years and an average onset age of 38 years. When the dose accumulation of radon and its daughters exceeds 120 working level day (WLM), the incidence rate begins to increase, and when it exceeds 1800WLM, it is significantly increased by 20 ~ 30 times. Exposure of rats to the gas and dust in these mines will induce lung tumors. The number of Japanese atomic bomb survivors suffering from lung cancer has greatly increased. Bibby's lifelong tracking of Hiroshima atomic bomb survivors found that the number of survivors who were less than 1400m from the explosion center was significantly higher than those who were less than 1400 ~ 1900 m and 2000m from the explosion center.
4. Past chronic lung infection
For example, in patients with pulmonary tuberculosis and bronchiectasis, in the process of chronic infection, bronchial epithelium may metaplasia into squamous epithelium, which may lead to cancer, but this situation is rare.
5. Genetic and other factors
There may also be family aggregation, decreased genetic susceptibility and immune function, metabolic and endocrine dysfunction.
It plays an important role in the occurrence of lung cancer. Many studies have proved that genetic factors may play an important role in people and/or individuals susceptible to environmental carcinogens.
6. Air pollution
The high incidence of lung cancer in developed countries is mainly due to air pollution caused by harmful substances such as benzopyrene carcinogenic hydrocarbons produced by asphalt pavement dust after the combustion of oil, coal and internal combustion engines in developed industries and transportation areas. Air pollution and smoking may promote each other and play a synergistic role in the pathogenesis of lung cancer.
Diffusion and metastasis of lung cancer
1. Direct diffusion
Tumors near the periphery of the lung can invade the visceral pleura, and cancer cells fall off into the pleural cavity, forming implantation metastasis. The central tumor or the tumor near the surface of mediastinum can invade the visceral pleura, chest wall tissue and mediastinal organs.
2. Blood transfer
Cancer cells can migrate to any part of the body after they return to the left heart with pulmonary veins. Common metastatic sites are liver, brain, lung, skeletal system, adrenal gland, pancreas and other organs.
3. Lymphatic metastasis
Lymphatic metastasis is the most common metastasis route of lung cancer. Cancer cells invade lymph nodes around adjacent lung segments or lobar bronchi through lymphatic vessels around bronchi and pulmonary vessels, then reach hilum or carina lymph nodes, then invade mediastinal and paratracheal lymph nodes, and finally involve supraclavicular or cervical lymph nodes.
clinical picture
The clinical manifestations of lung cancer are complicated. The presence and severity of symptoms and signs, and the symptoms and signs that appear depend on the location, pathological type, metastasis and complications of the tumor, as well as the differences in patients' response and tolerance. The early symptoms of lung cancer are often mild, even without any discomfort. Central lung cancer symptoms appear early and severe, while peripheral lung cancer symptoms appear late and mild, or even asymptomatic, and are often found during physical examination. Symptoms of lung cancer can be roughly divided into: local symptoms, systemic symptoms, extrapulmonary symptoms, infiltration and metastasis symptoms.
(A) local symptoms
Local symptoms refer to the symptoms caused by stimulation, obstruction, infiltration and compression of the tissue when the tumor itself grows locally.
1. Cough
Cough is the most common symptom, with cough as the first symptom accounting for 35% ~ 75%. Cough caused by lung cancer may be related to intrathoracic complications such as changes in bronchial mucus secretion, obstructive pneumonia, pleural invasion and atelectasis. When the tumor grows in the bronchial mucosa with a large diameter and is sensitive to external stimuli, it can produce a cough similar to that caused by foreign body-like stimuli, which is typically manifested as paroxysmal irritating dry cough, and general cough drugs are often difficult to control. When the tumor grows in the small bronchial mucosa below the segment, the cough is not obvious, or even does not cough. For patients who smoke or suffer from chronic bronchitis, if the degree of cough increases, the frequency changes and the nature of cough changes, such as high-pitched metallic sound, especially the elderly, we should be highly alert to the possibility of lung cancer.
2. Blood in sputum or hemoptysis
Blood in sputum or hemoptysis is also a common symptom of lung cancer, accounting for about 30% of the first symptoms. Because of the rich blood supply and fragile texture of tumor tissue, blood vessels rupture when coughing violently, leading to bleeding, and hemoptysis may also be caused by local tumor necrosis or vasculitis. The characteristics of hemoptysis in lung cancer are intermittent or persistent, and a small amount of sputum is bloodshot or a small amount of hemoptysis is repeated. Occasionally, it is difficult to control massive hemoptysis due to the rupture of large blood vessels, the formation of large cavities or the tumor breaking into bronchial and pulmonary vessels.
3. Chest pain
Chest pain as the first symptom accounts for about 25%. Often manifested as irregular dull pain or dull pain in the chest. In most cases, peripheral lung cancer invades parietal pleura or chest wall, which can cause severe intermittent pleural pain. If it continues to develop, it will turn into constant pain. Mild chest discomfort that is difficult to locate is sometimes related to central lung cancer invading mediastinum or involving blood vessels and peripheral bronchial nerves, while 25% patients with malignant pleural effusion complain of chest pain. Persistent and severe chest pain is not easily controlled by drugs, which usually indicates extensive pleural or chest wall invasion. Persistent pain in the shoulder or chest and back suggests the possibility of tumor invasion near the mediastinum in the lung lobe.
4. Chest tightness and shortness of breath
About 10% patients take this as the first symptom, which is more common in central lung cancer, especially in patients with poor lung function. The main causes of dyspnea are as follows: ① In the late stage of lung cancer, mediastinal lymph nodes are widely metastasized, and when the trachea, carina or main bronchus are compressed, symptoms of shortness of breath and even suffocation may occur. ② A large amount of pleural effusion compresses lung tissue. When mediastinum is seriously displaced or pericardial effusion exists, chest tightness, shortness of breath and dyspnea may occur, but the symptoms can be relieved after aspiration. (3) Diffuse bronchioloalveolar carcinoma and disseminated bronchial adenocarcinoma reduce the breathing area, cause gas diffusion dysfunction, lead to serious imbalance of ventilation/blood flow ratio, and gradually aggravate dyspnea, often accompanied by cyanosis. ④ Others: including obstructive pneumonia. Atelectasis, lymphatic lung cancer, tumor microembolization, upper respiratory tract obstruction, spontaneous pneumothorax and chronic lung diseases such as COPD.
Step 5 be harsh
There are 5% ~ 18% lung cancer patients with hoarseness as the first complaint, usually accompanied by cough. Hoarseness generally suggests direct invasion of mediastinum or lymphadenopathy, involving ipsilateral recurrent laryngeal nerve and leading to left vocal cord paralysis. Vocal cord paralysis can also cause different degrees of upper airway obstruction.
(2) Systemic symptoms
1. fever
The first symptom is 20% ~ 30%. Lung cancer causes fever for two reasons. One is inflammatory fever. When the tumor of central lung cancer grows, it often blocks the opening of lung segment or bronchus first, causing corresponding obstructive pneumonia or atelectasis of lung lobe or lung segment, leading to fever, but it is mostly around 38℃ and rarely exceeds 39℃. Antibiotic treatment may be effective and the shadow may be absorbed. However, due to poor drainage of secretions, it often recurs, and it can occur in about13 patients in a short time. Peripheral lung cancer usually causes fever in the late stage, because the tumor compresses the adjacent lung tissue and causes inflammation. Secondly, cancer fever is mostly caused by the absorption of tumor necrosis tissue by the body. This kind of fever anti-inflammatory drugs are ineffective, and hormones or indole drugs have certain curative effects.
2. emaciation and cachexia
In the late stage of lung cancer, loss of appetite caused by infection and pain, increased consumption caused by tumor growth and toxins, and increased levels of cytokines such as TNF and leptin in the body can cause severe emaciation, anemia and cachexia.
(3) Extrapulmonary symptoms
Because some special active substances (including hormones, antigens, enzymes, etc. ) is caused by lung cancer, and patients may have one or more extrapulmonary symptoms, which often appear before other symptoms, and may fade or appear with the growth and decline of the tumor. Pulmonary osteoarthropathy is common in clinic.
1. Pulmonary osteoarthropathy
The clinical manifestations are tussah-shaped fingers (toes), periosteum hyperplasia at the distal end of long bones, new bone formation, swelling, pain and tenderness of the affected joints. Tibial ribs, humerus and metacarpal bones are the most common long bones, and joints such as knees, ankles and wrists are more common. The incidence of tussah fingers and toes is about 29%, mainly squamous cell carcinoma; The incidence of proliferative osteoarthropathy is 1% ~ 10%, which is mainly found in adenocarcinoma and rare in small cell carcinoma. The exact reason is not completely clear, which may be related to estrogen, growth hormone or neurological function. After surgical resection, the tumor can be relieved or subsided, and it can reappear when it recurs.
2. Tumor-associated ectopic hormone secretion syndrome
About 10% patients can have such symptoms, which can be manifested as the first symptom. Other patients have no clinical symptoms, but can detect one or more plasma ectopic hormones. This symptom is more common in small cell lung cancer.
(1) ectopic ACTH secretion syndrome
Because the tumor secretes ACTH or ACTH-releasing factor active substances, plasma cortisol increases. Clinical symptoms are similar to Cushing's syndrome, including progressive myasthenia, peripheral edema, hypertension, diabetes, hypokalemic alkalosis and so on. It is characterized by the rapid progress of the course of disease, serious mental disorders, accompanied by skin pigmentation, but centripetal obesity, sanguine and purple stripes are not obvious. This syndrome is more common in lung adenocarcinoma and small cell lung cancer.
(2) Ectopic gonadotropin secretion syndrome
It is caused by the spontaneous secretion of LH and HCG by tumors, which stimulates the secretion of gonadal steroids. Most of them are bilateral or unilateral breast development in men, which can occur in various cell types of lung cancer, especially undifferentiated cancer and small cell cancer. Occasionally, abnormal erection of penis can be seen, which is not only related to abnormal hormone secretion, but also may be caused by penile vascular embolism.
(3) ectopic parathyroid hormone secretion syndrome
It is caused by parathyroid hormone or osteolytic substance (polypeptide) secreted by tumor. The clinical manifestations are hypercalcemia and hypophosphatemia, and the symptoms include anorexia, nausea, vomiting, abdominal pain, polydipsia, weight loss, tachycardia, arrhythmia, irritability and insanity. More common in squamous cell carcinoma.
(4) Ectopic insulin secretion syndrome
The clinical manifestations are subacute hypoglycemia syndrome, such as insanity, hallucination and headache. The reason may be related to the tumor consuming a lot of glucose, secreting body fluids similar to insulin activity or secreting insulin-releasing peptides.
(5) Carcinoid syndrome is caused by the secretion of 5- hydroxytryptamine by tumor. It is characterized by bronchospasm asthma, skin flushing, paroxysmal tachycardia and watery diarrhea. It is more common in adenocarcinoma and oat cell carcinoma.
(6) neuromuscular syndrome (Eton-Lambert syndrome)
It is caused by the arrow-shaped substance secreted by the tumor. It is characterized by random muscle weakness and extreme fatigue. It is more common in small cell undifferentiated carcinoma. Others include peripheral neuropathy, spinal ganglion cells and neurodegeneration, subacute cerebellar degeneration, cortical degeneration, polymyositis and so on. , can cause limb pain and weakness, dizziness, nystagmus, ataxia, walking difficulties and dementia.
(7) Ectopic growth hormone syndrome is characterized by hypertrophic osteoarthropathy, which is more common in adenocarcinoma and undifferentiated carcinoma.
(8) syndrome of abnormal secretion of antidiuretic hormone
It is caused by a large amount of ADH secreted by cancer tissue or polypeptide substances with antidiuretic effect. Its main clinical feature is hyponatremia, accompanied by low osmotic pressure of serum and extracellular fluid (
MOsm/L), continuous renal excretion, urine osmotic pressure is greater than plasma osmotic pressure (urine specific gravity >; 1.200) and water poisoning. More common in small cell lung cancer.
3. Other performances
(1) Skin damage
Echinodermosis nigricans and dermatitis are more common in adenocarcinoma, and skin pigmentation is caused by melanocyte stimulating hormone (MSH) secreted by tumor, which is more common in small cell carcinoma. Others include scleroderma and hyperkeratosis of palmoplantar skin.
(2) All types of lung cancer in cardiovascular system can have abnormal coagulation mechanism, including wandering venous embolism, phlebitis and non-bacterial embolic endocarditis, which can occur several months before the diagnosis of lung cancer.
(3) Blood system
There may be chronic anemia, purpura, polycythemia and leukemia-like reaction. It may be caused by reduced iron absorption, shortened life span of erythropoiesis disorder and capillary hemorrhagic anemia. In addition, DIC can appear in lung cancer of various cell types, which may be related to the release of procoagulant factors by tumors. Patients with lung squamous cell carcinoma may be accompanied by purpura.
(d) symptoms of invasion and metastasis
1. Lymph node metastasis
The most common are mediastinal lymph nodes and supraclavicular lymph nodes, mostly on the same side of the lesion, a few on the opposite side, mostly hard, single or multiple nodules, and sometimes you can see a doctor first. Lymph nodes beside trachea or under carina are enlarged, which can compress airway and cause chest tightness. Shortness of breath or even suffocation. Dysphagia may occur when the esophagus is compressed.
2. Pleural invasion and/or metastasis
Pleura is a common site of invasion and metastasis of lung cancer, including direct invasion and implantation metastasis. Clinical manifestations vary with the presence or absence of pleural effusion and the amount of pleural effusion. The causes of pleural effusion include not only direct invasion and metastasis, but also the obstruction of lymph nodes and the accompanying obstructive pneumonia and atelectasis. Common symptoms include dyspnea, cough, chest tightness and chest pain, or no symptoms at all; Physical examination shows that the intercostal space is full, the intercostal space is widened, the breathing sound is reduced, the voice twitching is reduced, the palpation is firm, and the mediastinum is displaced. Pleural effusion can be serous, serous or bloody, and most of them are exudates. Malignant pleural effusion is characterized by rapid growth and is mostly bloody. Spontaneous pneumothorax can occur in extremely rare lung cancer, and its mechanism is direct invasion of pleura and rupture of obstructive emphysema, which is more common in squamous cell carcinoma and has a poor prognosis.
3. Superior vena cava syndrome (SVCS)
The tumor directly invades or mediastinal lymph node metastasis oppresses the superior vena cava, or intraluminal embolization makes it narrow or occluded, which leads to blood reflux disorder and a series of symptoms and signs, such as headache, facial edema, varicose veins of neck and chest, increased pressure, dyspnea, cough, chest pain and dysphagia, and often faints or dizziness when bending over. Compensatory varicose veins in the chest and upper abdomen reflect the time and anatomical location of superior vena cava obstruction. The symptoms and signs of superior vena cava obstruction are related to its location. If an anonymous vein is blocked, the blood flow in the head, face and neck can return to the heart through the opposite anonymous vein, and the clinical symptoms are mild. If the superior vena cava is blocked below the entrance of azygos vein, in addition to the above vein dilatation, there is also abdominal vein dilatation, and blood flows into the inferior vena cava in this way. If the obstruction develops rapidly, brain edema may occur, accompanied by headache, lethargy, irritability and changes in consciousness.
4. Renal metastasis
About 35% of patients who died of lung cancer found renal metastasis, which is also the most common metastatic site for patients who died within 1 month after lung cancer resection. Most renal metastases have no clinical symptoms, and sometimes they can be manifested as low back pain and renal insufficiency.
5. Digestive tract metastasis
Liver metastasis can be manifested as loss of appetite, pain in the liver area and sometimes nausea. Serum γ-GT is often positive, and AKP gradually increases. During physical examination, the liver can be found to be swollen, hardened and nodular. Small cell lung cancer is prone to pancreatic metastasis, which may lead to pancreatitis or obstructive jaundice. Lung cancer of various cell types can metastasize to liver, gastrointestinal tract, adrenal gland and retroperitoneal lymph nodes, which are mostly asymptomatic in clinic and often found in physical examination.
6. Bone metastasis
The common sites of bone metastasis of lung cancer are ribs, vertebrae, ilium and femur. , but ipsilateral ribs and vertebrae are more common, showing local pain with fixed-point tenderness and tapping pain. Spinal metastases can compress the spinal canal, leading to obstruction or compression symptoms. Joint involvement can lead to joint cavity effusion, and puncture may find cancer cells.
7. Central nervous system symptoms
(1) brain, meninges and spinal cord metastasis
The incidence rate is about 10%, and its symptoms may be different according to different metastatic sites. The common symptoms are increased intracranial pressure, such as headache, nausea, vomiting and mental state changes. Rare symptoms include seizures, cranial nerve involvement, hemiplegia, ataxia, aphasia and sudden fainting. Meningeal metastasis is not as common as brain metastasis, and often occurs in patients with small cell lung cancer, and its symptoms are similar to brain metastasis.
(2) Encephalopathy and cerebellar cortical degeneration
Encephalopathy is mainly manifested as dementia, psychosis and organic diseases, while cerebellar cortical degeneration is characterized by acute or subacute limb dysfunction, difficulty in limb movement, tremor, dysphonia and dizziness. It has been reported that the above symptoms can be alleviated after tumor resection.
8. Heart invasion and metastasis
It is not uncommon for lung cancer to involve the heart, especially central lung cancer. Tumors can invade the heart through direct dissemination, or they can spread retrograde through lymphatic vessels, blocking the drainage lymphatic vessels of the heart and causing pericardial effusion. Slow development can be asymptomatic, or only pain in precordial area, under costal arch or upper abdomen. Those who develop rapidly may have typical symptoms of pericardial tamponade, such as impatience, palpitation, neck and face vein dilatation, enlarged heart boundary, low heart sound, hepatomegaly and ascites.
9. Symptoms of peripheral nervous system
Horner syndrome is caused by cancer oppression or invasion of cervical sympathetic nerve, which is characterized by pupil contraction, ptosis, enophthalmos and facial anhidrosis. When the brachial plexus is compressed or invaded, it causes the brachial plexus compression sign, which is characterized by burning radiation pain, local paresthesia and nutritional atrophy of the ipsilateral upper limb. When the tumor invades the phrenic nerve, it can be approved that the diaphragm is paralyzed, chest tightness and shortness of breath occur, and there is contradictory movement of the diaphragm under X-ray fluoroscopy. When the recurrent laryngeal nerve is compressed or invaded, it can cause vocal cord paralysis and hoarseness. Lung apex tumor (superior sulcus tumor) invades the cervical 8, thoracic 1 nerve, brachial plexus, sympathetic ganglion and adjacent ribs, causing severe shoulder and arm pain, paraplegia or weakness of one arm and muscular atrophy, which is called pan-coast syndrome.
diagnose
1.x-ray examination
Through X-ray examination, we can know the location and size of lung cancer, and we can see local emphysema, atelectasis or infiltrative lesions or lung inflammation near the focus caused by bronchial obstruction.
2. Bronchoscopy
Through bronchoscope, we can directly observe the pathological changes of endobronchial membrane and lumen. Tumor tissue can be taken for pathological examination, or bronchial secretions can be taken for cytological examination to make a clear diagnosis and determine histological types.
3. Cytological examination
Sputum cytology is a simple and effective method for general survey and diagnosis of lung cancer. Most patients with primary lung cancer can find exfoliated cancer cells in sputum. The positive rate of sputum cytology in central lung cancer can reach 70% ~ 90%, while that in peripheral lung cancer is only about 50%.
4. Thoracotomy and exploration
If after various examinations and short-term diagnostic treatment, the nature of lung mass is still unclear and the possibility of lung cancer cannot be ruled out, then thoracotomy should be performed. This can avoid delaying the illness and make lung cancer patients lose the opportunity of early treatment.
5.ECT inspection
ECT bone imaging can find bone metastasis earlier. X-ray and bone imaging have positive findings. If the osteogenic reaction in the lesion is static and the metabolism is inactive, the bone imaging is negative and the X-ray is positive. The two complement each other and can improve the diagnostic rate. It should be noted that the false positive rate of ECT bone imaging in the diagnosis of bone metastasis of lung cancer can reach 20% ~ 30%, so those with positive ECT bone imaging need MRI scanning of the bones in the positive area.
6. Mediastinoscopy
Mediastinoscopy is mainly used for mediastinal lymph node metastasis, which is not suitable for surgical treatment, and other methods can not obtain pathological diagnosis of patients. Mediastinoscopy should be performed under general anesthesia. A transverse incision was made in the suprasternal recess, and the soft tissue in front of the neck was bluntedly separated to reach pretracheal space, and then it was bluntedly released from the anterior tracheal passage. An observation mirror was placed behind the innominate artery to observe the swollen lymph nodes near the trachea, tracheobronchial angle and carina, and the lymph nodes were dissected and dissected with special biopsy forceps for pathological examination.
The diagnosis basis of primary bronchogenic carcinoma includes: symptoms, signs, imaging manifestations and sputum cancer cell examination.
The differential diagnosis of typical lung cancer is easy to differentiate, but in some cases, lung cancer is easily confused with the following diseases:
1. Tuberculosis
Tuberculosis, especially tuberculoma (ball) should be differentiated from peripheral lung cancer. Tuberculoma (tuberculoma) is more common in young patients, with a long course of disease, and blood in sputum is rare, and mycobacterium tuberculosis is found in sputum. Imaging is mostly round, which is seen in the upper tip or posterior segment. Small volume, less than 5cm in diameter, smooth boundary, uneven density and calcification. There are often scattered tuberculosis lesions around the tuberculoma, which are called satellite lesions. Peripheral lung cancer is more common in patients over 40 years old, with blood in sputum, and the positive rate of cancer cells in sputum is 40% ~ 50%. X-ray chest film tumors are often lobulated, with irregular edges, small burr shadows, pleural shrinkage and rapid growth. In some cases of chronic pulmonary tuberculosis, lung cancer can occur on the basis of pulmonary tuberculosis, and further sputum cytology and bronchoscopy must be done, and thoracotomy should be performed if necessary.
2. Lung infection
Pulmonary infection is sometimes difficult to distinguish from obstructive pneumonia caused by lung cancer blocking bronchi. However, if pneumonia occurs in the same place many times, we should be vigilant and highly suspect that it is caused by tumor blockage. We should take sputum from patients for cytological examination and fibrotracheal examination. In some cases, it is difficult to distinguish it from peripheral lung cancer when the lung inflammation is partially absorbed and the remaining inflammation is wrapped by fibrous tissue to form nodules or inflammatory pseudotumors. Thoracotomy should be performed on suspicious cases.
3. Benign lung tumor
Benign lung tumors: such as structural tumors, chondromas, fibromas, etc. It is rare, but it must be differentiated from peripheral lung cancer. Benign tumors have a long course of disease and are mostly asymptomatic in clinic. On the X-ray film, it is often a round block with neat edges, no burrs and no leaves. Bronchial adenoma is a low-grade malignant tumor, which occurs mostly in young women. Therefore, clinical symptoms such as pulmonary infection and hemoptysis often appear, and diagnosis can often be made through fiberoptic bronchoscopy.
4. Malignant lymphoma of mediastinum (lymphosarcoma and Hodgkin's disease)
Symptoms such as cough and fever often appear in clinic. Imaging findings show that mediastinal shadow is widened and lobulated, which is sometimes difficult to distinguish from central lung cancer. If there is supraclavicular or axillary lymph node enlargement, biopsy should be done to confirm the diagnosis. Lymphosarcoma is particularly sensitive to radiotherapy, and low-dose radiotherapy can be tried for suspicious cases, which can obviously shrink the tumor. This experimental treatment is helpful for the diagnosis of lymphosarcoma.
treat cordially
(1) chemotherapy
Chemotherapy is the main treatment for lung cancer, and more than 90% of lung cancer needs chemotherapy. The curative effect of chemotherapy on small cell lung cancer is positive in both early and late stages, and even about 1% of early small cell lung cancer is cured by chemotherapy. Chemotherapy is also the main treatment for non-small cell lung cancer, and the tumor remission rate of chemotherapy for non-small cell lung cancer is 40% ~ 50%. Chemotherapy can not cure non-small cell lung cancer, but can only prolong the survival time and improve the quality of life of patients. Chemotherapy is divided into therapeutic chemotherapy and adjuvant chemotherapy. Chemotherapy needs to choose different chemotherapy drugs and different chemotherapy schemes according to different histological types of lung cancer. Chemotherapy can not only kill tumor cells, but also damage normal cells of human body, so chemotherapy needs to be carried out under the guidance of oncologists. In recent years, the role of chemotherapy in lung cancer is no longer limited to patients with inoperable advanced lung cancer, but is often included in the comprehensive treatment plan of lung cancer as systemic treatment. Chemotherapy can inhibit the decline of bone marrow hematopoietic system, mainly leukocytes and platelets, and can be treated with granulocyte colony stimulating factor and platelet stimulating factor. Chemotherapy is divided into therapeutic chemotherapy and adjuvant chemotherapy.
(2) Radiotherapy
1. Treatment principles
Radiotherapy has the best effect on small cell lung cancer, followed by squamous cell carcinoma and adenocarcinoma. The irradiation field of radiotherapy for lung cancer should include the primary focus and mediastinum with lymph node metastasis. At the same time, it should be supplemented by drug treatment. Squamous cell carcinoma is moderately sensitive to radiation, mainly local invasion and relatively slow metastasis, so radical treatment is often used. Adenocarcinoma is insensitive to radiation and easy to metastasize in blood, so radiotherapy alone is rarely used. Radiotherapy is a local treatment, which often requires combined chemotherapy. The combination of radiotherapy and chemotherapy can adopt synchronous radiotherapy and chemotherapy or alternate radiotherapy according to different patients' conditions.
2. Classification of radiotherapy
According to the purpose of treatment, it is divided into radical treatment, palliative treatment, preoperative neoadjuvant radiotherapy, postoperative adjuvant radiotherapy and intracavitary radiotherapy.
3. Complications of radiotherapy
Complications of radiotherapy for lung cancer include radiation pneumonia, radiation esophagitis, radiation pulmonary fibrosis and radiation myelitis. The above radiotherapy-related complications are positively correlated with radiotherapy dose, and there are also individual differences.
(3) Surgical treatment of lung cancer
Surgical treatment is the first choice and the most important treatment for lung cancer, and it is also the only treatment that can cure lung cancer. The purpose of surgical treatment of lung cancer is:
Complete resection of the primary focus and metastatic lymph nodes of lung cancer to achieve clinical cure;
Resection of most tumors creates favorable conditions for other treatments, that is, tumor reduction surgery;
Volume reduction surgery: suitable for a small number of patients, such as refractory pleural cavity and pericardial effusion. The clinical symptoms caused by pericardium and pleural effusion can be cured or alleviated by removing pleura and pericardium implanted nodules and removing part of pericardium and pleura, thus prolonging life or improving quality of life. Tumor reduction surgery requires both local and systemic chemotherapy. Surgical treatment often requires adjuvant chemotherapy and radiotherapy before or after operation to improve the cure rate and survival rate of patients. The five-year survival rate of surgical treatment for lung cancer is 30% ~ 44%. The mortality rate of surgical treatment is 1% ~ 2%.
1. Surgical indications
Surgical treatment of lung cancer is mainly suitable for early and middle stage (Ⅰ ~ Ⅱ stage) lung cancer, Ⅲ a stage lung cancer and partial selective Ⅲ b stage lung cancer with tumor confined to one side of the chest.
(1) stage Ⅰ and Ⅱ lung cancer;
(2) stage 2)IIIa non-small cell lung cancer;
(3) The lesion is confined to one side of the chest, and some stage Ⅲ b non-small cell lung cancer can be completely resected;
(4) (4) The number of patients with stage IIIA and part IIIb lung cancer has decreased after preoperative neoadjuvant chemotherapy;
(5) Non-small cell lung cancer with single metastasis (i.e. brain, adrenal gland or liver) can be completely resected if both the primary tumor and the metastatic tumor are suitable for surgical treatment and there are no surgical contraindications;
(6) Non-small cell stage Ⅲ b lung cancer with tumor invading pericardium, great vessels, diaphragm and trachea carina was diagnosed, and distant or/and micrometastasis was ruled out by various examinations, and the focus was localized. The patient has no physiological surgical contraindications, and the tumor invading tissues and organs can be completely removed;
2. Contraindications for surgery
(1) stage Ⅳ lung cancer has extensive metastasis.
(2) Multiple groups of patients with mediastinal lymph node metastasis, especially patients with invasive mediastinal lymph node metastasis;
(3) Stage Ⅲ B lung cancer with contralateral hilar or mediastinal lymph node metastasis;
(4) Patients with severe visceral dysfunction who cannot tolerate surgery;
(5) Patients with hemorrhagic diseases that cannot be corrected.
3. Selection of surgical methods for lung cancer
The principle of surgical resection is: completely remove the primary focus and lymph nodes that may metastasize in the chest cavity, preserve normal lung tissue as much as possible, and be careful in total lung resection.
(1) Wedge-shaped and local resection of lung refers to wedge-shaped tumor resection and partial pneumonectomy. It is mainly suitable for early lung cancer with small size, old age and infirmity, poor lung function or good cancer differentiation and low malignancy;
(2) pneumonectomy is anatomical pneumonectomy. Mainly suitable for the elderly, peripheral isolated early lung cancer with poor cardiopulmonary function, or part of central lung cancer whose focus is limited to the root of lung cancer;
(3) Lobectomy
Lobectomy is suitable for peripheral and partial central lung cancer with lung cancer confined to one lobe, and the central lung cancer must ensure that there is no cancer residue in the bronchial stump. If lung cancer involves two lobes or intermediate bronchi, upper and lower Ye Quan pneumonectomy is feasible;
(4) Bronchial sleeve lobectomy
This operation is mainly suitable for central lung cancer with lung cancer located in the opening of lobar bronchus or middle bronchus. The advantages of this operation are that it not only realizes the complete resection of lung cancer, but also preserves healthy lung tissue;
(5) Sleeve lobectomy of bronchopulmonary artery.
This operation is mainly suitable for central lung cancer with lung cancer located at the opening of lobar bronchus or intermediate bronchus and lung cancer invading pulmonary trunk. Surgery requires not only bronchial resection and reconstruction, but also pulmonary trunk resection and reconstruction. The advantages of this operation are that it not only realizes the complete resection of lung cancer, but also preserves healthy lung tissue;
(6) Tracheal carina resection and reconstruction
When the lung tumor exceeds the main bronchus and involves carina or tracheal sidewall but not more than 2cm, tracheal carina resection and reconstruction or sleeve pneumonectomy can be performed. If one lobe is still preserved, we should strive for resection and reconstruction of tracheal carina with preserved lobe.
(7) pneumonectomy
Pneumonectomy refers to unilateral pneumonectomy, that is, right or left pneumonectomy, which is mainly suitable for lung cancer with good cardiopulmonary function, extensive lesions and younger age, and is not suitable for lobectomy or sleeve lobectomy. The incidence and mortality of complications in pneumonectomy are high, and the long-term survival rate and quality of life of patients are not as good as those in pneumonectomy. Therefore, surgical indications must be strictly controlled.
4. Surgical treatment of recurrent lung cancer
Recurrent lung cancer includes local residual cancer recurrence after operation and new second primary lung cancer. For patients with recurrence of residual cancer of bronchial stump, we should strive for reoperation, bronchial sleeve plasty and resection of residual cancer.
For the second primary lung cancer after complete resection of lung cancer, as long as the lung cancer is suitable for surgical treatment, the patient's visceral function can tolerate reoperation and there are no surgical technical problems, thoracotomy should be considered to remove the recurrent lung cancer.