Importance of colorectal cancer screening

Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society's estimates for the number of colorectal cancer cases in the United States for 2013 are:

• 102,480 new cases of colon cancer
• 40,340 new cases of rectal cancer
• the lifetime risk for developing colorectal cancer is about 1 in 20 (5.1%). This risk is slightly higher in men than in women. A number of other factors (described in the section, "Risk factors for colorectal cancer") may also affect a person's risk for developing colorectal cancer.

Colorectal cancer is the third leading cause of cancer-related deaths in the United States when men and women are considered separately, and the second leading cause when both sexes are combined. It is expected to cause about 50,830 deaths during 2013.

The death rate (the number of deaths per 100,000 people per year) from colorectal cancer has been dropping for more than 20 years. There are a number of likely reasons for this. One is that polyps are being found by screening and removed before they can develop into cancers. Screening also allows more colorectal cancers to be found earlier, when the disease is easier to cure. In addition, treatment for colorectal cancer has improved over the last several years. As a result, there are now more than 1 million survivors of colorectal cancer in the United States.

Regular colorectal cancer screening or testing is one of the most powerful weapons for preventing colorectal cancer. Screening is the process of looking for cancer in people who have no symptoms of the disease.

From the time the first abnormal cells start to grow into polyps, it usually takes about 10 to 15 years for them to develop into colorectal cancer. Regular screening can, in many cases, prevent colorectal cancer altogether. This is because some polyps, or growths, can be found and removed before they have the chance to turn into cancer. Screening can also result in finding colorectal cancer early, when it is highly curable.

Several tests are used to screen for colorectal cancer in people with an average risk of colorectal cancer. Ask your doctor which tests are available where you live and which options might be right for you.

People who have no identified risk factors (other than age) should begin regular screening at age 50. Those who have a family history or other risk factors for colorectal polyps or cancer (see section, “Risk factors for colorectal cancer”) should talk with their doctor about starting screening when they are younger and/or getting screened more frequently.