What You Need to Know About Colon Cancer

Why screening could save your life, plus tips for lowering your risk.

Posted on | By Sharecare
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An In-Depth Look at the Colon (3:37)

Colon cancer is the second leading cause of cancer death in the U.S., with about 50,000 people dying due to colon cancer each year. This disease is so often deadly because it’s frequently discovered after it’s already reached an advanced stage.

“Colon cancer is potentially very curable if we screen for it according to guidelines,” says Steven Goldin, MD, a surgical oncologist at Fawcett Memorial Hospital in Port Charlotte, Florida. 

Here’s how to recognize the signs of colon cancer, when to book your next screening appointment, plus tips to lower your risk.

Symptoms of colon cancer


Colon cancer begins in the lower part of your intestine. “Most colon cancers, especially the smaller tumors, have no symptoms at all,” says Goldin. “People will be walking around with no idea that they have multiple tumors. Often, they don’t get tested until there’s not much that can be done to treat them.”

By the time symptoms show, the disease has usually already spread outside of the colon. Yet, between 70 to 90 percent of colon cancers are diagnosed after symptoms appear because of the tendency to put off screening.

If symptoms are present, they may include:

Black or tarry stools, diarrhea

Severe constipation or being completely unable to have a bowel movement

Frequent gas pain or stomach aches

Blood in your stool: “Anybody who's experiencing rectal bleeding should make an appointment with their healthcare provider (HCP). People might think, ‘Well, I've got hemorrhoids,’ but you could have colon cancer as well,” says Goldin.

Internal bleeding can also cause you to feel weak, exhausted or dizzy. If you’re experiencing any of these symptoms, make an appointment with your HCP immediately.

Colon cancer screening


If you’re at an average risk for colon cancer, you should have your first colonoscopy at age 50. People who are at a higher risk should talk to their HCP starting around age 40 to determine an appropriate screening regimen for them, says Goldin. You’re at a higher risk and may need to start screening before age 50 if you:

Are African American

Have a history of Crohn’s disease or ulcerative colitis

Have a family history of colon cancer

There are a number of tests available, but the gold standard for colon cancer screening is the colonoscopy, explains Goldin. For a colonoscopy, a gastroenterologist, a doctor specializing in the stomach and intestines, will advance a long tube with a camera through your colon to search for polyps. Polyps are little growths on the colon lining, which may eventually grow into tumors.

If you have polyps, your gastroenterologist will remove samples and send them to a lab to determine if you have cancer, called a biopsy. He or she may be able to completely remove polyps or even small tumors during the colonoscopy as well.

Article written by Sharecare
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