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Screening for colon cancer: what you need to know

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, 5 min read

Screening for colon cancer: what you need to know

We don’t usually discuss poop in polite conversation. For the topic of screening for colon cancer, however, we’re going to suspend the rules.

About two years ago, I noticed a little blood in my poop. I mentioned it to my doctor. She told me it was time to get a colonoscopy1 anyway. But the blood stopped and I was busy. When the bleeding came back and didn’t stop, I made an appointment with a gastroenterologist for a colonoscopy. A colonoscopy is a test where the doctor uses a camera to look inside the large intestine. Don’t worry; it's a very small camera. And, most importantly, you are asleep. It doesn’t hurt.

I was 100% certain that it was going to be something harmless, such as hemorrhoids. I wasn’t in pain. I had a normal appetite and wasn’t losing weight. No one in my family had had colon cancer, and I wasn’t even 50 years old. Annoyed, I drank the magnesium citrate and MiraLAX and spent the day in the bathroom.

When I woke up from the anesthesia after the colonoscopy, I was shocked when the doctor said there was a tumor. He didn’t say polyp, or lump, or even “small mass,” The blood, he said, was coming from a 3.5 centimeter tumor in my colon that was “very suspicious for malignancy.” That’s doctor speak for “I’m almost certain it’s cancer.”

Update: I’m fine now but Iearned the importance of screening

I had to have surgery to remove part of my colon. They used a robot, which was really cool. And while I have to be checked every year, I’m fine now. I also know that if I had waited longer, it would have been much worse. Had I gone for a colonoscopy 4 years ago, when I was 45, it’s possible the polyp could have been removed without major surgery.

I’m saying all of this to drive home the importance of colorectal cancer screening.2 It’s one of those diseases where a screening test (a test on someone without any symptoms at all), can find the problem early so that it can be prevented!

How does colon cancer screening work?

Colorectal is a fancy word for the large intestine. When we eat, the food travels down from our mouths through the esophagus and into the stomach. From there it goes to the small intestine. That’s where the nutrients we need are taken into the blood and pumped through the body. The final stop is the large intestine, where whatever is left over becomes poop.

Most colon cancers start out as polyps. These are tiny bumps on the inside of the colon that can be removed during a colonoscopy. And once they are gone, they can’t turn into cancer. Doctors are working on ways to find them earlier and earlier.

One way to look for early changes is a special stool (or poop) test that looks for blood (because cancer usually bleeds). There is also another test that looks for cancer DNA. These tests are easy and accurate, and if the results are abnormal, a colonoscopy is needed.

The colon has to be completely empty for the doctor to get a good look during the procedure. So the day before a colonoscopy, you can’t eat any solid food and have to take a prescription of a high dose of laxatives to get all of the poop out of the colon. Not going to lie, there are better ways to spend an afternoon. But it’s not bad. (My personal tip: I go to the Chinese restaurant that makes good soup and get a large container of wonton broth!)

Who should have colon cancer screening?

The stool test is good for people who do NOT have symptoms and are not high risk. It should be done every year, starting at age 45. The stool DNA test, on the other hand, should be repeated every 3 years. If the stool test is abnormal, or if a person is high risk (see below), then they need a colonoscopy.

In the United States, the U.S. Preventive Services Task Force (USPSTF3) recommends that people at average risk of colorectal cancer begin regular screening at age 45. Regular screening should continue for people in good health through age 75.

In the UK, bowel cancer screening begins for most people at age 604. Free screening kits are available every two years between the ages of 60 and 74 by calling the free helpline on 0800 707 60 60.

For screening, people are considered to be at average risk5 if they do not have:

  • A personal history of colorectal cancer or certain types of polyps
  • A family history of colorectal cancer
  • A personal history of inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
  • A confirmed or suspected hereditary colorectal cancer syndrome, such as familial adenomatous polyposis (FAP) or Lynch syndrome (hereditary non-polyposis colon cancer or HNPCC)
  • A personal history of getting radiation to the abdomen (belly) or pelvic area to treat a prior cancer

How often a colonoscopy is done also depends on if there are polyps (repeat in 3-5 years) or if it is normal (repeat in 5-10 years). If you are 45 or older, and you have never been screened for colon cancer, talk to your doctor about which test is right for you.

Read the first article in this series on breast cancer screening.

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The information provided is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Seek the advice of a doctor with any questions you may have regarding a medical condition. Never delay seeking or disregard professional medical advice because of something you have read here.

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