• The American Cancer Society (ACS) estimated that in 2005 there would be 172,570 new cases of lung cancer and 163,510 deaths. This indicates a cure rate of roughly 5%.

• The ACS further projects that in 2006, lung cancer will kill 73,020 women and 90,470 men.
• Early-stage lung cancer does not have any symptoms. Therefore, lung cancers are rarely discovered until they have progressed to a late stage where they are almost untreatable. In contrast with the typical low cure rate, it is known that cancers found in the early stage are highly curable. CT screening finds over 80% of lung cancers in this early stage.

Lung cancer background

Lung cancer is the leading cause of death from cancer in both men and women in the United States, killing more people than cancers of the breast, colon, cervix and prostate combined. In the year 2005, it was estimated that there would be over 163,510 deaths in the United States alone; worldwide, more than a million die from it every year. Lung cancer has one of the worst prognoses of all cancers, with an overall cure rate of 5%. Major risk factors for lung cancer include tobacco use and certain environmental carcinogen exposures. Tobacco is associated with 87% of all cases of cancer of the lung, trachea, and bronchus.

Lung cancer usually does not cause any symptoms until it has reached an advanced stage, when treatment is least likely to work. Early Stage I lung cancer discovered through early detection screening, however, has a cure rate of 70%, and for some subgroups it is even higher.

There is now renewed hope in the detection of lung cancer when it is in its early, most curable stage, due to the compelling evidence that suggests that CT screening can lead to high cure rates of lung cancer.

What is lung cancer?

To understand lung cancer, we must first understand the lungs. The lungs are two sponge-like organs in the chest. The right lung has three sections, called lobes. The left lung has two lobes. It is smaller because the heart takes up more room on that side of the body. The lungs bring air in and out, taking in oxygen and getting rid of carbon dioxide gas, which is a waste product of the body.

The lining which surrounds the lungs is called the pleura. The pleura protects the lungs. The windpipe or the trachea brings air down into the lungs, and divides into tubes called bronchi, which divide into smaller branches called bronchioles. At the end of these small branches are tiny air sacs known as alveoli.

Most lung cancers start in the lining of the bronchi. But lung cancer can also begin in other areas such as the trachea, bronchioles, or alveoli. Lung cancer usually takes many years to develop.

What causes lung cancer?

About 87% of lung cancer is caused by smoking. The lung cells of smokers go through changes that can lead to lung cancer. The longer a person has been smoking, and the more packs per day they've smoked, the greater their risk is of developing lung cancer.

People who work with asbestos also have a higher risk of getting lung cancer. If they smoke as well, the risk is greatly increased.

Besides smoking and asbestos, there are other risk factors for lung cancer. These include certain cancer-causing agents in the environment, aging, and lung scarring from some types of pneumonia.

Some people have never smoked and never worked with asbestos, nor ever been exposed to any known cancer-causing agents; yet, they still get lung cancer. There are unknown factors, and there is no sure way to prevent it.

What are the first warning signs of lung cancer?

Early-stage lung cancer does not usually have any symptoms. However, the following symptoms may eventually appear as the cancer progresses:

• A cough that does not go away
• Weight loss and loss of appetite
• Chest pain
• Fever without a known reason
• Hoarseness
• Bloody or rust-colored sputum (spit or phlegm)
• Shortness of breath
• Recurring infections such as bronchitis and pneumonia

If you have any of the above mentioned symptoms, talk to your doctor right away. For more signs and symptoms of lung cancer, please visit our FAQ page.