Journal of Leukemia
Open Access

Effects of Lung Cancer Around the World

Twain M^{* *}Correspondence: Twain M, Department of Oncology, University of California, United States, Email:

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Editorial

Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale.

Lung cancer is the leading cause of cancer deaths worldwide. People who smoke have the greatest risk of lung cancer, though lung cancer can also occur in people who have never smoked. The risk of lung cancer increases with the length of time and number of cigarettes you've smoked. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer.

When you breathe in, air enters through your mouth or nose and goes into your lungs through the trachea windpipe. The trachea divides into tubes called bronchi, which enter the lungs and divide into smaller bronchi. These divide to form smaller branches called bronchioles. At the end of the bronchioles are tiny air sacs known as alveoli.

The alveoli absorb oxygen into your blood from the inhaled air and remove carbon dioxide from the blood when you exhale. Taking in oxygen and getting rid of carbon dioxide are your lungs’ main functions. Lung cancers typically start in the cells lining the bronchi and parts of the lung such as the bronchioles or alveoli.

A thin lining layer called the pleura surrounds the lungs. The pleura protect your lungs and help them slide back and forth against the chest wall as they expand and contract during breathing. Below the lungs, a thin, dome-shaped muscle called the diaphragm separates the chest from the abdomen. When you breathe, the diaphragm moves up and down, forcing air in and out of the lungs.

About 80% to 85% of lung cancers are NSCLC. The main subtypes of NSCLC are adenocarcinoma, squamous cell carcinoma, and large cell carcinoma.

These subtypes, which start from different types of lung cell are grouped together as NSCLC because their treatment and prognoses are often similar.

Adenocarcinomas start in the cells that would normally secrete substances such as mucus. Adenocarcinoma is usually found in the outer parts of the lung and is more likely to be found before it has spread.

The principal function of the lungs is to exchange gases between the air we breathe and the blood. Through the lung, carbon dioxide is removed from the bloodstream and oxygen enters the bloodstream. The right lung has three lobes, while the left lung has two lobes and a small structure called the lingual that is the equivalent of the middle lobe on the right. The major airways entering the lungs are the bronchi, which arise from the trachea.

Lung cancers can arise in any part of the lung, but 90%-95% of cancers of the lung arise from the epithelial cells, the cells lining the larger and smaller airways (bronchi and bronchioles); for this reason, lung cancers are sometimes called bronchogenic cancers or bronchogenic carcinomas. (Carcinoma is another term for cancer.) Cancers also can arise from the pleura (called mesotheliomas) or rarely from supporting tissues within the lungs, for example, the blood vessels.

Radon is a colorless and odorless gas generated by the breakdown of radioactive radium, which in turn is the decay product of uranium, found in the Earth's crust. The radiation decay products ionize genetic material, causing mutations that sometimes become cancerous. Radon is the second mostcommon cause of lung cancer in the US.

Asbestos can cause a variety of lung diseases such as lung cancer. Tobacco smoking and asbestos both have synergistic effects on the development of lung cancer.