Why are Colonoscopies so Important?

Cancer Q&A

By James K.V. Willson, M.D.

Colon cancer is highly curable if caught early, and the best way to detect colon cancer is through a colonoscopy.

There are two main reasons why proper screening for colon cancer is so critical. First, if cancer is found, surgical intervention is most effective when it’s caught early. But even more important is that precancerous polyps—called adenomas­—can be identified by colonoscopies and then removed, which prevents their progression to cancer.

A recent study in The New England Journal of Medicine, appearing just in time for Colon Cancer Awareness Month (March), underscores the importance of colonoscopies in rather dramatic fashion. We believed from previous studies that colonoscopies decrease the death rate associated with colon cancer. This latest study proves it. The death rate was cut in half among those who had colonoscopies and whose doctors removed precancerous growths.

James K.V. Willson, MD, Director, Simmons Cancer Center
James K.V. Willson, M.D.
Director, Simmons Cancer Center

The screening guidelines, generally speaking, are straightforward. For people at normal risk of colon cancer, screening should begin at age 50. A clean bill of health means the patient doesn’t need another colonoscopy for 10 years.

There are exceptions, which typically lead to individual screening plans. If you’re found to have an adenoma, for example, then follow-up colonoscopies should occur much sooner and more often.

Additionally, if you have a sibling or parent with a history of colon cancer or polyps, the general recommendation is to have your first colonoscopy at least 10 years earlier than the age at which your relative was found to be at risk. Patients with a strong family history or genetic predisposition to colon cancer should know they can develop cancer at a young age and need to be screened.

The tragedy to me is that there are still so many deaths from colon cancer, even though it’s so highly preventable. Despite the high cure rate, it remains the No. 3 cancer killer in the United States among men and women. The American Cancer Society estimates that more than 49,000 Americans died from colon cancer in 2011.

We have to get better about complying with recommendations for colonoscopies and understanding how truly effective they are. We still have some real barriers to overcome when it comes to access and compliance, but colonoscopies remain the gold standard for screening.