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Over 50? Don't Put Off Colon Cancer Screening

This year, more than 145,000 people in the United States will be diagnosed with colorectal cancer, and nearly 60,000 will die from the disease. The number two cause of cancer deaths in this country, it's one of the most treatable cancers if found early.

What Is Colorectal Cancer?

Most colorectal cancers begin with benign growths or polyps in cells lining the colon. A polyp is a growth that projects from the lining of the intestine or rectum. Polyps are usually noncancerous. They may cause painless rectal bleeding or bleeding not apparent to the eye. These growths can become cancerous, invading the colon wall and eventually moving into blood vessels and spreading to other body areas.

How Quickly Do Polyps Grow?

It usually takes about five years for a polyp to reach 1/2 inch in diameter, and an additional 5 to 10 years for a 1/2 inch polyp to turn cancerous. Symptoms may not show up for another 5 to 10 years, often too late to cure.

What Are Common Symptoms?

Frequently there are no symptoms. But the following changes MIGHT indicate colon cancer:

How Is Colon Cancer Detected?

"Screening is the best way to find polyps before they become cancers, or to find colorectal cancers early," says colon and rectal surgeon Samuel Oommen, M.D., on staff at John Muir Medical Centers, Walnut Creek and Concord campuses.

Talk with your doctor about screening options which include a fecal occult blood test (stool sample), flexible sigmoidoscopy, double contrast barium enema, and colonoscopy. If results of the fecal occult test are positive, other diagnostic testing is performed.

Who Should Be Screened?

The American Cancer Society (ACS) recommends that average-risk adults should begin colorectal cancer screening at age 50, utilizing one of the following five options for screening: (1) annual fecal occult blood test (FOBT) or fecal immunochemical test (FIT); (2) flexible sigmoidoscopy every 5 years; (3) annual FOBT or fecal immunochemical test plus flexible sigmoidoscopy every 5 years; (4) colonoscopy every 10 years; or (5) double-contrast barium enema every five years.

Persons at high risk need earlier and more frequent screening. If polyps are found with flexible sigmoidoscopy or a barium enema, a colonoscopy is usually performed to remove the polyps and to make sure other polyps or cancer are not present.

How Is A Fecal Occult Blood Test Done?

This test can easily be done at home with one of several convenient methods of collecting a small stool sample. The ACS recommends collecting two samples from consecutive bowel movements. The test detects blood usually not visible to the eye, by chemical means.

What Is Flexible Sigmoidoscopy?

Flexible sigmoidoscopy can be done by a trained primary care physician. Performed without sedation in the physician's office, it takes only a few minutes and is easily tolerated. The procedure can detect about two-thirds of polyps and over half of colorectal cancers.

What Is A Colonoscopy?

Colonoscopy provides visualization, biopsy and removal of polyps. A lighted flexible tube is threaded through the colon to examine the lining thoroughly.

"Colonoscopy is done under intravenous sedation, which makes the procedure comfortable for the healthy patient," says gastroenterologist Will Lane, M.D., on staff at John Muir Medical Center, Walnut Creek Campus.

How Can Colorectal Cancer Be Prevented?

You can help prevent colorectal cancer if you:

The Future Looks Brighter

"Mortality rates from colon cancer have dropped since 1991, probably due to increased screenings and newer diagnostic and therapeutic technologies," Dr. Oommen notes.

The National Institutes of Health urges everyone over 50 to have their colons checked. Consult with your physician for the screening option best for you.

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