Colorectal Cancer Screening Prevents Cancer, Saves Lives

By Marijke Vroomen Durning,

Tuesday, April 14, 2015

A patient lies on an exam table while doctors in scrubs prepare to perform a colonoscopy.

Regular colonoscopy screenings can help prevent colorectal cancer. That’s because colonoscopies allow doctors to look for and remove precancerous growths called polyps. While preparation for this screening procedure may cause some people discomfort, it’s a precautionary measure that could save your life.

  • Colorectal cancer can be prevented with screening.
  • Screening looks for precancerous growths called polyps.
  • Colonoscopy is the gold standard among screening methods.
  • The preparation can be the most difficult part of a colonoscopy.
  • Alternative methods include virtual colonoscopy and the stool DNA test.

Screening for colorectal cancer saves lives. This message couldn’t be any clearer, says Robert Kurtz, Chief of Memorial Sloan Kettering’s Gastroenterology and Nutrition Service. “We can prevent colon cancer.”

Most types of screening, such as mammograms and skin checks, look for cancer after it’s already developed, with the goal of finding it as early as possible. Colorectal cancer screening, though, looks for precancerous signs, such as fleshy growths called polyps. By removing these growths, your doctor can actually prevent cancer from developing.

Colorectal cancer is the third most common and second most deadly cancer among adults in the United States. And while there has been an almost 30 percent reduction in deaths over the past several years, since the push for screening began, that statistic could be much better. About one-third of Americans between the ages of 50 and 75 — the group at highest risk for colorectal cancer — have not been screened, according to the Centers for Disease Control.

Preparing for Screening

Why are so many people not being screened? For one thing, colonoscopy, the most effective method for colorectal cancer screening, requires preparation. To do a colonoscopy, your doctor inserts a colonoscope, a long tube with a camera and light on one end. This tube moves through your colon and sends images back to a screen. If your doctor sees a polyp, he or she can very likely remove it right away and send it to the lab for testing. Most people who have a colonoscopy receive an anesthetic and don’t remember the procedure at all.

However, prepping for a colonoscopy isn’t comfortable for some people, Dr. Kurtz explains. It involves having to take strong laxatives to completely clean out your colon. This is important so your doctor can see the colon walls and any suspicious spots.

MSK recommends colonoscopy once every ten years for people age 50 and older who are at average risk for colorectal cancer. Those at higher risk because of family history or other factors may need to have them more frequently and before age 50. Learn more about our screening recommendations for colorectal cancer.

“If the patient hasn’t done an adequate job of preparing the colon, we’re going to be missing things,” Dr. Kurtz adds. “You can’t really see anything or see small polyps if there’s a lot of residual stool left behind.”

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Other Screening Methods

For some, a virtual colonoscopy is a better choice for screening than standard colonoscopy. It still requires the same preparation, but it uses CT images to see the colon walls instead of a colonoscope and no anesthetic is needed. A small tube is inserted into the rectum during the procedure in order to push air into the colon, making it bigger and easier to visualize using the CT scanner.

Virtual colonoscopies are good for detecting suspicious spots, says Dr. Kurtz. But if any polyps are found, you still need to have a regular colonoscopy to have them removed. This means having to do the prep twice if the second colonoscopy can’t be done right away.

Screening really can save your life.
Robert Kurtz Chief of Gastroenterology and Nutrition Service

While there are no other exams as effective at finding colorectal cancer or polyps as colonoscopy, there are two other types of tests that may help detect signs of cancer: the fecal occult blood test and the stool DNA test. Both check for blood in the stool; the DNA test also looks for DNA mutations that could mean there is something going on inside the colon. Both tests can only tell if something suspicious is showing, however. If they’re positive, you still need a colonoscopy to find out exactly what the tests found.

“The DNA test is coming along. There are some good papers that suggest that it’s very worthwhile,” Dr. Kurtz says.

The bottom line, says Dr. Kurtz, is that patients need to speak with their doctors about screening, no matter which type of test they choose. “Screening really can save your life.”

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“The DNA test is coming along." Come on! The Cologaurd DNA test would have saved my life! No I am not dead but I have been fighting Stage IV Colon Cancer for 8.5 years, not fun.

I was pro-active I thought. I had a colonoscopy at 45, asked my doctor for one at 50, he convinced me I didn't need one, asked again at 55 and he agreed but I MISSED the appointment and never rescheduled got busy with life and was diagnosed with Colon Cancer at 62. I would NOT have missed an appointment with Cologuard if it had been available. I would have had regular test every three years not TEN!

You think a colonoscopy is better than Cologuard. Not in my opinion. The test people will take it better. The test that is non-invasive is better. I think the false positives of Cologuard will turn out to be positives that colonoscopies miss. Cologuard does not cause perforations and the occasional death. Cologuard finds cancers colonoscopies miss. Yes colonoscopies do miss. Maybe colonoscopies should be vetted by Cologuard instead of the other way around.

Big fan of Cologuard and MSK where I received my first treatments for Colon Cancer many years ago.

Say hi to Dr. Stadler

I was diagnosed with early stage colon cancer in 2010 at the age of 48. I went to MSKCC for a second opinion and met Dr Temple. Her, her staff and the hospital treated me with the utmost care and concern. After I was re-diagnosed 4 months after my first surgery, Dr Temple made me a priority and we went in for a second surgery, followed by chemo. I have other friends who are battling cancer, and they don't receive near the care that I received at Sloan. Simply the best!

I was diagnosed with stage 4 colon cancer that had metastasized to my liver at the age of 58. I came to MSKCC and met with Dr. Nancy Kemeny. I feel truly blessed to have been treated by this amazing oncologist and her phenomenal team. It is now over seven years since my diagnosis and I have been cancer free for almost five years! Dr. Kemeny and her amazing team always gave me hope and because of them I was able to remain positive throughout my treatment. I will forever be grateful to Dr. Kemeny, her team and MSKCC!!

I was diagnosed with stage IV colorectal cancer in 2005 at the age of 51. After surgery and 10 months of chemo, I returned to living life fully. 10 years cancer-free! I have such deep respect and appreciation for the doctors, nurses and staff at MSKCC.

Dear Stephen, thank you so much for sharing your positive experience! We are glad to know you continue to be cancer-free and that you felt well-cared for by your medical team at MSK. Happy holidays!

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