Lung cancer: causes and treatment
Determination of lung cancer: lung cancer, tumors, developing from the epithelial tissue of the bronchi, or alveoli, the small part of a mesenchymal and neurogenic origin (pleural mesothelioma, sarcoma, neuroblastoma). Currently, lung cancer ranks first in the structure of cancer. The frequency of lung cancer in men aged 48 - 77 years higher than in women. Etiology: 1. The wide prevalence of smoking and air pollution, 2. Occupational hazards (dust, chemical carcinogens, the effect of low doses of ionizing radiation), 3. Air pollution compounds of arsenic, chlorine, cadmium, 4. Contribute to the development of cancer chronic lung disease (tuberculosis, bronchitis, different scar lung tissue changes) 5. Genetic risk factors. Pathogenesis. In humans distinguish six main types of epithelial cells in the bronchi, which can be transformed in the process of carcinogenesis in cancer: 1. Flashing cell 2. Glandulotsitov that produce mucus, 3. Basal cells, 4. Thyroid cells 5. Shpilkopodibni apocrine cells of terminal bronchioles, 6. Kulchitsky neurosecretory cells that produce biogenic amines and polypeptides. The appearance of tumors in the lung preceded precancerous changes: epidermoid metaplasia of bronchial epithelium, hyperplasia, proliferation of the epithelium, the formation of mikropapilom, intraepithelial carcinoma, scars with chronic lung diseases (tuberculosis, heart disease, inflammation, mechanical damage). Classification. The International Classification of Diseases, Injuries and Causes of Death X revision (1992), lung cancer is in the category C 34 C34 - Malignant neoplasm of bronchus and lung C34.0 - Main bronchus Carina Trachea Lung C34.1 - Upper part of the bronchus or lung C34.2 - High proportion of the bronchus, or lung C34.3 - of lower lobe bronchus, or lung C34.8 - The defeat of the bronchi and lungs, which overlaps the localization C34.9 - the bronchi or lung, unspecified primary lung tumor cells out of the bronchopulmonary tissue, pleura, secondary develop from listed bloodstream or lymphatic tumor cell metastasis, as well as growing into the bronchi, lungs and pleura of the tumor from adjacent organs and tissues. Prior to cancer of the lungs and pleura include cancer, pleural mesothelioma and various types of sarcomas. According to the International Classification of lung tumors share: I. Squamous or epidermal (epidermoid) carcinoma. II. Small cell lung cancer: ovsyannokletochny (limfotsitopodobnyh). Promizhnoklitinny. The combined oat cell. III. Adenocarcinoma: acinar papillary bronchoalveolar carcinoma Solid carcinoma with mucin formation IV. Large cell carcinoma: Giant. clear cell. V. Ferruginous - squamous cell carcinoma. VI. Carcinoid tumor. VII. Cancer of bronchial glands: Adenokistozny, Mukoepidermoidny, Other. VIII. Other tumors. Clinical classification of TNM. T - Primary tumor. THEN - the primary tumor is not detected, T and S - preinvasive carcinoma (carcinoma in situ); T1 - the tumor is not more than 3 cm, surrounded by lung tissue or visceral pleura, without apparent invasion proximal - lobular bronchus during bronchoscopy, T2 - tumor more than 3 cm or tumor of any size, which is accompanied by atelectasis or obstructive pneumonia fate, which covers the root of the lung. The proximal edge of the tumor is located not less than 2 cm from the Carina, T3 tumor of any size directly passing on the adjacent anatomical structures, or the tumor is less than 2 cm from the Carina, a tumor with concomitant obstructive atelectasis or pneumonia, or the entire lung with hemorrhagic effusion; Tx - any swelling, which can be detected, or tumor proven cytologically, but invisible X-ray and bronchoscopic. N - Regional lymph nodes (hilar lymph nodes) N0 - no evidence of regional lymph nodes. N1 - there is NO damage bronchial and (or) the lymph nodes of the root of lung on the affected side, including direct tumor spread to the lymph nodes. N2 - affected mediastinal lymph nodes. N3 - insufficient data to assess the status of lymph nodes. M - distant metastasis. M0 - no evidence of distant metastases. M1 - there are distant metastases. M - not enough data to determine distant metastases. Grouping of lung cancer in stages: 1) Hidden Cancer - Stage T NM0 first T1 N0M0 stage 1b N0T2 T1 N1M0 Stage 2 Stage 3 T2 N1M0 T3 N0-1 Mo, T0 -3 N2M0 Stage 4 T0-3 N0-2 Examples of formulations of diagnosis of M1 . 1. The central small cell lung cancer with a lesion of the right lung and main bronchi verhnodolovogo, pleura of the right lung with metastases to the liver, brain. 2. Peripheral cancer (adenocarcinoma) IV segment of the left lung with metastasis to lymph nodes in the mediastinum, left supraclavicular region (T2, N 2M1). 3. Squamous cell carcinoma of the bronchus with atelectasis verhnodolovogo upper lobe and metastases in bronchopulmonary and tracheobronchial lymph nodes (T2, N 1M0) 4. Bronchoalveolar carcinoma of the left lung diffusely - nodular form, with the defeat of the lower lobe (T2 N 0M0). The clinic. Symptoms of lung cancer is determined by tumor localization in the lungs, the prevalence of the process and the absence of disease, which often precede the development of lung cancer. When a peripheral cancer early symptoms are: cough (initially dry, then with little sputum), chest pain on the affected side (60 - 70%). As the progression of the disease in the clinic symptoms associated with damage to large areas of broncho-pulmonary tissues, organs germination in the mediastinum, chest wall, diaphragm, and the development of specific pleurisy, the collapse of the tumor, with the detection of metastases, tumor growth intoxication. Sometimes direct clinical evidence of lung cancer is the enlarged lymph nodes supraclavicular regions, laryngeal paralysis due to recurrent nerve lesion, the appearance of metastases in the subcutaneous tissue, pathological fractures. A special place in the clinic for lung cancer took peraneoplastichni syndromes that may occur during the initial stages of tumor growth, osteoarthropathy, a syndrome of "drumsticks", gynecomastia, rheumatoid syndrome, hypercalcemia, hyponatremia, which is associated with the production of lung cancer in hormone-like substances. X-ray examination, even if asymptomatic can be suspected neoplastic process: identify tumor lesions, signs of bronchial patency, secondary symptoms of pneumonic changes around the tumor in the lung tissue, enlarged lymph nodes at the root of the lungs and mediastinum. Bronchioloalveolar carcinoma was relatively slow. Patients report cough, chest pain, shortness of breath. Informative X-ray method by which reveal a peripheral tumor, multiple tumor nodules or pnevmoniepodibni changes of the lungs. The methods of verification of the tumor is sputum on tumor cells and transthoracic needle biopsy. Diagnosis and differential diagnosis of lung cancer diagnoz.V used a complex X-ray examination, which involves the use of radiography, tomography, pnevmomediastinografiya, angiopneumography, computed tomography, or CT-based nuclear magnetic resonance. To evaluate the lung ventilation is used with radiopnevmografiyu He133, which allows to identify a reduced area of pneumatization in different zones of the lungs. Bronchoscopy allows a cytological and histological studies to establish the spread of tumors bronchial tree. Among other endoscopic mediastinoscopy and thoracoscopy is used. Mediastinoscopy is indicated for detection of mediastinal lymph nodes, suspicious for metastatic disease. Thoracoscopy allows to exclude pleural metastases, facilitates the differential diagnosis of pleural mesothelioma. When treating patients with cancer need clear histologic or cytologic diagnosis. In difficult diagnostic cases, a particular value is the systematic examination of sputum for abnormal cells. The final procedure in the case of uncertain diagnosis in some cases becoming diagnostic thoracotomy. In recent years, widely used radioimmunoassay tests certain cancers - embryonic antigen (CEA), calcitonin, and β2 - microglobulin concentration in the blood of patients with lung cancer is much higher than normal concentration. Differential diagnosis of lung cancer should be conducted with benign tuberculoma, a cyst of the lung. For benign tumors of the lung characterized by low-key, asymptomatic onset of the disease, the lack of general weakness, shortness of breath, chest pain, and only later show signs of compression of other organs. Hematological changes, in contrast to lung cancer detected отсутствуют.Рентгенологически rounded shadow with smooth contours, the lymph nodes were not enlarged. Growth is very slow or absent. Cytologically as opposed to lung cancer, which exhibit atypical and cancer cells in sputum, and punctate in benign lung tumors exhibit the same type of cells, monomorfnist structure of cells, mitoses are absent. For pulmonary tuberculosis is characterized by gradual onset with moderate currents, symptoms of tuberculosis intoxication, moderate sedimentation rate and leukocytosis. Radiological: roundish inhomogeneous shadow, signs of TB (focal calcification). Growth is slow or absent. Verhnodoleva localization process. Cytology: epithelioid cells (10-20%). Cyst lung is characterized by subtle asymptomatic onset, absence of clinical symptoms that may occur as a result of festering cysts (fever, sputum, cough). Hematological parameters are missing (except for the festering cysts). Radiographically: round or oval with a clear outline shadow. Positive syndrome Nemenova. Cytological data were normal. Treatment. There are surgical, combined (surgical + radiotherapy), radiotherapy, chemotherapy and holistic treatments for lung cancer. If no primary small cell lung cancer treatment - surgery. It was shown in I-II stages of the disease and to conduct pneumonectomy, lobectomy, or extended operations. In some cases, improve the results of treatment of patients with lung cancer allows preoperative and postoperative radiotherapy. Its use in patients with stage II-III cancer. Holding of combined treatment with the inclusion of radiotherapy obgrutovano high frequency of non-radical operations. Chemotherapy for small cell lung cancer is not used for patient refusal of other methods of treatment, or the inability of their prevalence in the process, as well as recurrence of disease when other treatments have been exhausted. Uses a combination active against lung cancer drug methotrexate, andriamitsinu, cyclophosphamide, tsispletinu, procarbazine, fluorouracil, mitomycin - C, vincristine. The combination of radiotherapy and chemotherapy in non-small cell lung cancer is used in a number of years. With small cell lung cancer surgery is used sparingly. Treated with radiotherapy or combined treatment (irradiation and polychemotherapy). When topically - common forms of treatment starts with chemotherapy, and then connect the radiation therapy. In cases of generalization and dissemination process, the main method is polychemotherapy. Polychemotherapy small cell lung cancer should be intense and long. The most effective drugs are etoposide, vincristine, natulan, embihin, methotrexate, cyclophosphamide, geksametilmelanin, adriamycin, mitomycin - C SSNU cisplatin. After achieving remission, maintenance therapy is needed, which takes place within 1-2 years. In the remission stage it makes sense to use immunomodulators: thymosin, T-activin, levamizol.U patients with remission showed prophylactic irradiation of the brain that is caused by a high frequency of micrometastases (in 25-60%), which until that time when clinical - radiological not investigated detected as cytotoxic agents in connection with the presence of blood-brain barrier can not always stop their development.