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Colorectal Cancer Facts

The colon is also known as the large bowel or large intestine. The rectum is the last 10-15 inches of the colon. The outlet of the rectum is the anus, the opening through which bowel movements pass.

What is colorectal cancer?

Virtually every colorectal cancer begins as an adenomatous polyp, a small benign growth arising from the mucosa, or the lining of the colon or rectum. These polyps grow slowly, taking three to five years to even become visible without the use of a microscope. It takes even longer, possibly as much as ten more years, for a cancer to develop from a polyp. Not all adenomatous polyps become cancers. But because there is no way to tell which will, virtually all are removed when diagnosed. Polyps located in the colon and rectum share the same growth potential

What are the symptoms of colorectal cancer?

Often there are no symptoms in the early stages of colorectal cancer.

Symptoms can include:

What are risk factors for colorectal cancer?

How can I decrease my risk of having colorectal cancer?

Are screening tests available?

What are screening guidelines?

Average Risk

Starting at age 50, those who are at average risk for colorectal cancer should have one of the five screenings every year:

Moderate Risk

Moderate risk are those who have a family history of colorectal cancer in a first degree relative or a personal history of polyps or colorectal cancer. Colorectal cancer in first degree relative under age 55 or two first degree relatives:

High Risk

High risk are those with a hereditary or genetic disposition for colorectal cancer and those with inflammatory bowel disease.

Family history of Familial adenomatous polyposis:

Flexible sigmoidoscopy and consideration for genetic counseling and testing beginning at age 12 to 14. Repeat sigmoidoscopy every one to two years.

Family history of hereditary nonpolyposis colon cancer:

Colonoscopy and consideration for genetic counseling and testing beginning at age 21 to 40. Repeat colonoscopy every two years and then yearly at age 40.

Inflammatory bowel disease:

Colonoscopy beginning at age 15 for left-sided colitis and age 8 for pancolitis. Repeat every one to two years.

The information provided are guidelines and not meant to be used as medical advice or replace the advice of your health care provider. It is important to discuss colorectal cancer with your health care provider