November 2018

Regular screening is one of the most powerful weapons for preventing colorectal cancer. Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in both men and women in the U.S. Even though we don’t know the exact cause of most colorectal cancers, it is possible to prevent many of them.

Screening is the process of looking for cancer or pre-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 most polyps can be found and removed before they turn into cancer. Screening can also find colorectal cancer early, when it is highly curable.

People who have no identified risk factors (other than age) should begin regular screening at age 50. If the screening shows no polyps or cancer, then it can be repeated in 10 years. Those who have a family history or other risk factors for colorectal polyps or cancer, such as inflammatory bowel disease, should talk with their doctor about starting screening at a younger age, about getting screened more frequently, and about which tests are best for them.

If you have a strong family history of colorectal polyps or cancer, you should talk with your doctor about it. While cancer in close (first-degree) relatives such as parents, brothers, and sisters is most concerning, cancer in more distant relatives can also be important. Having two or more relatives with colorectal cancer is more concerning than having one relative. It is also more concerning if your relatives were diagnosed with cancer at a younger-than-usual age, while less concerning if they were diagnosed at an advanced age.

You might benefit from genetic counseling to review your family medical tree to see how likely it is that you have a family cancer syndrome. The counselor can also help you decide if gene testing is right for you. People who have an abnormal gene can take steps to prevent colon cancer, such as getting screened at an early age or even having surgery.

Before getting genetic testing, it’s important to know ahead of time what the results may or may not tell you about your risk. This is why meeting with a genetic counselor or cancer genetics professional is crucial in deciding if genetic testing should be done.

Source: American Cancer Society