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Carcinoma lung The overwhelming majority of lung tumours are carcinomas. Most commonly, they arise from the pseudo-stratified epithelial lining of the bronchial airways but they can also arise from the epithelia of the smaller terminal airways and alveoli. Worldwide, lung cancer is the most common cause of cancer-related death. Types of lung cancer Lung cancer can be divided into two major types based on the appearance of lung cancer cells under the microscope.
Symptoms:
Causes and Prevention: Causes smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer-causing substances (carcinogens), changes in the lung tissue begin almost immediately. At first your body may be able to repair this damage. But with each repeated exposure, normal cells that line your lungs are increasingly damaged. Over time, the damage causes cells to act abnormally and eventually cancer may develop. Smoking:More than 15% of all lung cancer cases are small cell lung cancer. Small cell lung cancer is slightly more common in men than women.Almost all cases of SCLC are due to cigarette smoking. SCLC is rare in those who have never smoked. Passive smoking: Cigarette smoke containing the carcinogenic N -nitrosamines and aromatic polycyclic hydrocarbons can be inhaled passively by nonsmokers. Urinary levels of these carcinogens are 1-5% of those found in active smokers. Asbestos: Asbestos exposure has been shown to be strongly associated with the causation of lung cancer, malignant pleural mesothelioma, and pulmonary fibrosis. Prevention No active interventions to prevent lung cancer are proven effective except for smoking cessation (see Smoking Cessation). Remediation of high radon levels in private residences removes known cancer-promoting radiation, but a reduction in lung cancer incidence is unproven. Increasing dietary intake of fruits and vegetables high in retinoids and β-carotene appears to have no effect on lung cancer incidence. Vitamin supplementation is either unproven (vitamin E) or harmful (β-carotene) in smokers. Treatments
Treatment for lung cancer can involve surgical removal of the cancer, chemotherapy, or radiation therapy, as well as combinations of these treatments. The decision about which treatments will be appropriate for a given individual must take into account the location and extent of the tumor as well as the overall health status of the patient. Surgery: Surgical removal of the tumor is generally performed for limited-stage NSCLC and is the treatment of choice for cancer that has not spread beyond the lung. About 10%-35% of lung cancers can be removed surgically, but removal does not always result in a cure, since the tumors may already have spread and can recur at a later time. Chemotherapy :Both NSCLC and SCLC may be treated with chemotherapy. Chemotherapy refers to the administration of drugs that stop the growth of cancer cells by killing them or preventing them from dividing. Chemotherapy may be given alone, as an adjuvant to surgical therapy, or in combination with radiotherapy. Radiation therapy : Radiation therapy may be employed as a treatment for both NSCLC and SCLC. Radiation therapy uses high-energy X-rays or other types of radiation to kill dividing cancer cells
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