When you breathe in, air passes from your nose or mouth through the windpipe (trachea), which divides into two tubes (airways), one going to each lung. These are known as the right and left bronchus and they divide to form smaller tubes called bronchioles, which carry air through the lungs. At the end of the bronchioles are millions of tiny air sacs called alveoli. In the alveoli, oxygen is absorbed from air breathed in and passes into the bloodstream to be circulated around the body.Lung cancer is one of the most common types of cancer. The lungs are a pair of cone-shaped organs situated inside the chest, they bring oxygen into the body and take out waste carbon dioxide. There is a strong link between smoking and lung cancer. There are two main categories of lung cancer; Small Cell Lung Cancer (SCLC) , and Non-Small Cell Lung Cancer (NSCLC). World-wide over 1 million people are diagnosed with lung cancer each year.
Sometimes the instructions to a cell go haywire and that cell and its offspring reproduce wildly, without regard for the shape and function of a lung. That wild reproduction can form tumors that clog up the lung and make it stop functioning as it should. Because of the large size of the lungs, cancer may grow for many years, undetected, without causing suspicion. Lung cancer can spread outside the lungs without causing any symptoms.Adding to the confusion, the most common symptom of lung cancer, a persistent cough, can often be mistaken for a cold or bronchitis.
The main types of lung cancer are small cell lung carcinoma and non-small cell lung carcinoma. This distinction is important because the treatment varies; non-small cell lung carcinoma (NSCLC) is sometimes treated with surgery, while small cell lung carcinoma (SCLC) usually responds better to chemotherapy and radiation.The most common cause of lung cancer is long term exposure to tobacco smoke. The occurrence of lung cancer in non-smokers, who account for fewer than 10% of cases, appears to be due to a combination of genetic factors, radon gas, asbestos, and air pollution, including second-hand smoke.
Lung cancer is one of the most common cancers in the world. It is a leading cause of cancer death in men and women in the United States. Cigarette smoking causes most lung cancers. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk of lung cancer. High levels of pollution, radiation and asbestos exposure may also increase risk.
Cancer of the lung, like all cancers, results from an abnormality in the body's basic unit of life, the cell. Normally, the body maintains a system of checks and balances on cell growth so that cells divide to produce new cells only when needed. Disruption of this system of checks and balances on cell growth results in an uncontrolled division and proliferation of cells that eventually forms a mass known as a tumor.
Yet most lung cancer deaths could be prevented. That's because smoking accounts for nearly 90 percent of lung cancer cases. Your risk of lung cancer increases with the length of time and number of cigarettes you smoke. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer. Protecting yourself from other risk factors for lung cancer, such as exposure to asbestos, radon and secondhand smoke, also decreases your risk.