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Colorectal cancer: 7 candid questions about screening

Body, Cancer

Colorectal cancer is the third leading cause of cancer death in the U.S. Still, a lot of people don’t talk to their doctors about it. And let’s be honest: It does involve an intimate part of the body we tend to be squeamish about.

But colorectal cancer deserves a frank discussion — especially because it’s a cancer that can sometimes be prevented with a screening test.

So here are seven things you should know about colorectal cancer. At the very least, they might help you start your own frank discussion with your doctor.

1. What is colorectal cancer?

Colorectal cancer is cancer in your colon or rectum.

Your colon is part of your large intestine. It’s sometimes called the large bowel, and it’s about 5 feet long. It’s followed by the rectum and anal canal, which together are 6 to 8 inches long. The anal canal ends at the anus—the opening to the outside of your body.

2. Can changes in my stool be a sign of colorectal cancer?

It’s possible. Signs can include bright red or very dark stool or stools that are narrower than usual. Changes in bowel habits—like diarrhea or constipation—may also suggest colorectal cancer. But these can be signs of other conditions as well.

Keep in mind: Colorectal cancer symptoms often don’t appear until later in the disease. That’s why routine screening is so important. It can find cancer in its very early stages — before you have symptoms.

3. What’s a polyp?

A polyp is a growth on the inside wall of your colon. Some polyps may turn into cancer. Polyps that are larger than 1 centimeter are more likely to turn into cancer than smaller polyps. Suspicious polyps can be removed during a colonoscopy.

Your doctor may call your polyp an adenoma. That’s just a particular kind of polyp that develops on the lining of the large intestine. Most colorectal polyps are adenomas.

4. What happens during a colonoscopy?

A colonoscopy is an examination of your entire colon and rectum. The doctor uses a thin, flexible tube with a tiny video camera on the end. Called a colonoscope, it’s inserted in your anus and gently guided up through the colon. The scope’s camera sends images to a video screen.

If the doctor sees a polyp, he or she can remove it using a tool on the scope. The polyp is then sent to a lab to check for signs of cancer.

The entire exam takes about 30 minutes.

5. Is a colonoscopy painful?

Most people don’t find it painful. Some people feel discomfort.

Before the procedure, you’ll be given a sedative. Most people go to sleep and don’t remember the exam later. You’ll be drowsy, so you’ll need someone to drive you home afterward.

6. What’s the prep before the test like?

Many people consider the preparation for a colonoscopy the worst part of the procedure. You have to clean out your bowel so the doctor can see your colon clearly. That might involve going on a liquid diet for a day or two before the test, as well as avoiding certain foods and medicines.

You’ll also take medicines that make you go to the bathroom—a lot. So plan to be at home the day and night before your test if you can. You could still need to use the bathroom when you show up for the test. So don’t be embarrassed to ask for a restroom.

Frankly, the prep is unpleasant. But it’s a lot better than getting colorectal cancer.

7. Is a colonoscopy the only option?

There are other tests that screen for colorectal cancer. But a colonoscopy is the only one where doctors can remove polyps from the entire colon at the same time. Talk with your doctor about what’s best for you.

fecal occult blood test uses a small sample of your stool to look for blood that can’t be seen with the naked eye. You collect the stool at home and either take it to a lab or mail it in for testing.

sigmoidoscopy is like a mini-colonoscopy. It uses a shorter scope, so the doctor can view your rectum and less than half of your colon. It usually doesn’t require sedation.

virtual colonoscopy takes a series of x-rays (computed tomography) to look for polyps or other signs of cancer.

DNA stool test checks the cells in your stool for signs of cancer.

If any of these tests come back positive, you may need a colonoscopy to follow up.

Talk to your doctor about colorectal cancer screening

Most people should have their first colonoscopy at age 50. But if you are at higher risk, you may need to be screened sooner. Ask your doctor when you should start. Find an Adventist Health doctor.