| ancer is not just one disease but rather a group | | | | such as the trachea, bronchioles, or alveoli. Lung |
| of diseases. All forms of cancer cause cells in the | | | | cancer often takes many years to develop. Once |
| body to change and grow out of control. Most | | | | the cancer occurs, cancer cells can break away |
| types of cancer cells form a lump or mass called | | | | and spread to other parts of the body. |
| a tumor. Cells from the tumor can break away | | | | Cancer of the lung is a life- threatening disease |
| and travel to other parts of the body where they | | | | because it often spreads in this way before it is |
| can continue to grow. | | | | found. It is the leading cause of cancer death for |
| This spreading process is called metastasis. When | | | | both men and women. During the year 2000 |
| cancer spreads, it is still named after the part of | | | | there will be about 164,100 new cases of lung |
| the body where it started. For example, if breast | | | | cancer in this country. About 156,900 people will |
| cancer spreads to the lungs, it is still breast | | | | die of this disease: about 89,300 men and 67,600 |
| cancer, not lung cancer. | | | | women. |
| Another word for cancerous is malignant, so a | | | | More people die of cancer of the lung than of |
| cancerous tumor is referred to as malignant. But | | | | colon, breast, and prostate cancers combined. |
| not all tumors are cancer. A tumor that is not | | | | Lung cancer is fairly rare in people under the age |
| cancer is called benign. Benign tumors do not grow | | | | of 40. The average age of people found to have |
| and spread the way cancer does. They are | | | | cancer of the lungs is 60. If the cancer is found |
| usually not a threat to life. | | | | and treated by surgery early, before it has |
| A few cancers, such as blood cancers (leukemia), | | | | spread to lymph nodes or other organs, the |
| do not form a tumor. Most cancers are named | | | | five-year survival rate is about 42%. |
| after the part of the body where the cancer first | | | | However, few cancers of the lung are found at |
| starts. Lung cancer begins in the lungs. The lungs | | | | this early stage. The five-year survival rate for all |
| are two sponge-like organs in the chest. The right | | | | stages of lung cancer combined was 14% in 1995, |
| lung has three sections, called lobes. The left lung | | | | the last year for which we have national data. A |
| has two lobes. It is smaller because the heart | | | | risk factor is something that increases a person's |
| takes up more room on that side of the body. | | | | chance of getting a disease. Some risk factors, |
| The lungs bring air in and out of the body, taking | | | | like smoking, can be controlled. Others, such as a |
| in oxygen and getting rid of carbon dioxide gas, a | | | | person's age, can't be changed. |
| waste product. The lining around the lungs, called | | | | Smoking is by far the leading risk factor for lung |
| the pleura, helps to protect the lungs and allows | | | | cancer. More than 8 out of 10 diagnosed cancers |
| them to move during breathing. The windpipe | | | | of the lungs are thought to result from smoking. |
| (trachea) brings air down into the lungs. It divides | | | | The longer a person has been smoking, and the |
| into tubes called bronchi, which divide into smaller | | | | more packs per day smoked, the greater the |
| branches called bronchioles. At the end of these | | | | risk. If a person stops smoking before cancer |
| small branches are tiny air sacs known as alveoli. | | | | develops, the lung tissue slowly returns to normal. |
| Most cancers of the lungs start in the lining of the | | | | Stopping smoking at any age lowers the risk of |
| bronchi but they can also begin in other areas | | | | lung cancer. |