Lung Cancer Basics

What is lung cancer?

Lung cancer is an abnormal growth of cells in the lungs. If a lung cancer is not detected and treated early, it may spread to other areas of the body.

Is lung cancer common?

In the United States, lung cancer causes more deaths than any other cancer. United States Cancer Statistics reported that in 2007 over 200,000 people were diagnosed with lung cancer. In that year, nearly 160,000 people died of the disease.  Lung cancer annually accounts for more deaths than breast, cervical, colon and prostate cancer combined.

How can lung-cancer deaths be prevented?

With early diagnosis and treatment, the cure rate for lung cancer is high. Annual CT screenings can detect lung cancers in the earliest stage, when over 90 percent can be treated successfully. Early stage lung cancer presents with no symptoms, giving the undetected cancer an opportunity to grow and spread. By the time symptoms appear the cancer has reached a late stage, when treatment is difficult and the cure rate is significantly lower. Early detection and treatment improve the chances of a cure dramatically.

According to the results of the National Lung Screening Trial (NLST) published in New England Journal of Medicine (June 29, 2011), screening of heavy smokers with CT can decrease lung cancer mortality by 20% compared with chest x-ray.

How can lung cancer be detected?

Until recently, physicians had a limited variety of tests to detect lung cancer, and these were rarely sensitive enough to detect the cancer at an early stage. The tests were generally used only after symptoms appeared. Now, with the use of CT scans, patients at risk for lung cancer can be safely screened, before symptoms appear, enabling the detection of early, small lung cancers. Thus the possibility of a cure is greatly improved.

What are the causes of lung cancer?

Cigarette smoke is the most significant cause of lung cancer. The National Cancer Institute estimates that up to 90% of lung cancers are seen in smokers or former smokers . The longer a person has smoked, and the more cigarettes smoked, the higher the risk of developing lung cancer. To reduce lung cancer risks, don’t smoke. If you do smoke, quit.

Other causes include heavy exposure to materials such as asbestos, uranium, radon, arsenic and other carcinogens, or to secondhand smoke. Lung scarring from an earlier illness sometimes leads to the development of a lung cancer. Genetics can also predispose a person to lung cancer.

What about nonsmokers and lung cancer?

Approximately 10-15 percent of lung cancers occur in nonsmokers. We listed some possible causes above: exposure to carcinogens, a genetic predisposition, secondhand smoke exposure and lung scarring. Some other factors to consider are:

The lung-cancer risk may be higher if a blood-related parent or sibling has the disease, especially if the cancer was diagnosed at a young age. This may indicate that a genetic factor was involved.

Although more men die from lung cancer, research suggests that women of a similar age and with a similar smoking history as men are twice as likely to develop lung cancer.

The incidence of lung cancer and the lung-cancer death rates have been observed as higher among non-white patients. Initially thought to be due to higher smoking rates and the popularity of menthol cigarettes in this population, recent research suggests that other factors may be increasing the lung cancer risk in some groups.

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