Colorectal Cancer

Colorectal cancer is one of the most common cancers in the United Statestoday and the second-leading cause of cancer deaths in the United States. In many cases, colorectal cancer can be detected and prevented if simple steps are followed. The earlier the cancer or changes in the colon are found, the better the chance for cure.

Causes

No one knows the exact cause of colon cancer, but we do know some of the risk factors. Your chances of developing colon cancer are higher if you have any of the following:

• A history of ulcerative colitis, Crohn’s disease, or precancerous changes in the lining of the colon.

• A history of large polyps (growths in the colon) • A first-degree relative—mother, father, sister, or brother—who had colon cancer before 65 years of age

• Two first-degree relatives who had colon cancer at any age.

•  A history of breast, ovarian, or endometrial cancer Age also plays a role.

Most cases occur in people over 65 years of age. Fewer than 2 percent of cases occur in those individuals under 40 years of age.

Symptoms

You may not know you have colorectal cancer because there are no warning signs in the early stages of the disease. If you have a change in your bowel habit, such as bloody or black stools, your doctor will recommend that your colon be examined. The best way to know if you have colorectal cancer—before you have symptoms—is to be screened for the disease.

Screening for colon cancer

Don’t let worries of embarrassment or discomfort stop you from getting the screening you need. Early detection of colon cancer can save lives. Discuss these screening options with your doctor to decide the best method for you. Fecal Occult Blood Test (FOBT).This test detects the presence of blood in the stool, which is a warning sign for colorectal cancer. Many factors can interfere with the accuracy of this screening procedure, so follow-up testing is necessary to confirm positive results. If this method of screening is chosen, it is recommended that it be done once a year for people aged 50 to 80 years.

Flexible Sigmoidoscopy. For this test a thin, lighted tube is inserted into your rectum. With this device, your doctor can see about 27 inches into your colon, which is far enough to identify about 80 percent of cancers and polyps, because they tend to accumulate toward the lower end of your bowel. If this method of screening is chosen, it is recommended that it be done every five years for people aged 50 to 80 years.

Combination Flexible Sigmoidoscopy and FOBT. You and your doctor may decide to use both flexible sigmoidoscopy and FOBT to screen for colon cancer. This approach includes an annual FOBT and a flexible sigmoidoscopy every 5 years.

Total ColonEvaluation. A total colon evaluation can be done using a colonoscopy, colon X-ray alone, or a flexible sigmoidoscopy combined with a colon X-ray. A colonoscopy is similar to a flexible sigmoidoscopy, but allows your doctor to see the entire length of your colon. A colon X-ray or a flexible sigmoidoscopy combined with a colon X-ray is usually done every 5 years. A colonoscopy is usually done every 10 years.

CT Colonography. Using X-rays and a computer, CT colonography creates three-dimensional images of the interior surfaces of the entire colon. If an abnormality is found, a regular colonoscopy must be performed to remove it or take tissue samples for testing. CT colonography is an evolving research tool, and it is not yet known if it is as accurate as colonoscopy.

Prevention

• Get screened for colorectal cancer.

• Watch for warning signs. Talk to your doctor if you have black, bloody, or thin stools or if you have diarrhea or constipation that persists.

• Eat less fat. Obesity and diets that are high-fat or high-calorie have been linked to cancer in laboratory animals and humans. By cutting down on fatty foods, you can also reduce your calorie intake.

• Eat more high-fiber foods. Foods high in fiber include whole-grain cereals and breads, beans, fruits and vegetables, potatoes, and brown rice.