Colorectal cancer is far too common in the United States, but can be prevented through early screening. Colorectal cancer is the second leading cause of cancer deaths, according to the National Cancer Institute, with an estimated 140,000 new cases per year. About one in 20 Americans will develop colorectal cancer at some point during their lifetime.
This is one of very few cancers that we can actually prevent through regular health screening. Mammograms are important – but mammograms are for early detection of breast cancer, not prevention. Prostate checks are important, but they too are for early detection of prostate cancer, not prevention.
Colorectal cancer screening is different, and here is why: Colorectal cancer (cancer in the large intestine, including the colon and rectum) typically begins as precancerous growths, called polyps (or adenomas). It takes about ten years to go from the earliest precancerous stages to overt colon cancer. If you remove the precancerous polyps, then you can actually prevent cancer from developing. Pretty amazing.
Screening options
Screening, with either a colonoscopy or a stool test, is the only way to know whether you have a polyp or cancer. Most people do not have symptoms early on. Once you do develop symptoms (like blood in the stool, unexplained weight loss, change in stool caliber or persistent abdominal pain), it may be too late for prevention.
There are several ways to screen for colon cancer. You can do a stool test for occult blood, called a FIT test. You can have a stool DNA test to screen for polyps or cancer. You can have a sigmoidoscopy (which only looks at the last part of the colon and the rectum) plus a barium enema. But for most people, the best test is the colonoscopy. This involves passing a long flexible tube, about 1/2 inch in diameter, through the anus and up into the entire colon. A fiberoptic camera at the tip of the scope allows the doctor to see the colon wall, and special instruments used via the colonoscope allow for polyp removal. The colonoscopy takes 30 minutes or less, and medication is typically given intravenously so that you do not experience pain. In fact, many people do not even remember the test afterward.
Besides screening, what else can you do to prevent colorectal cancer? You can stop smoking, lose weight (if you are overweight), exercise regularly and watch your intake of alcohol and red meat. A diet that is high in vegetables, fruit and fiber can help decrease the risk of colorectal cancer.
Are you at risk?
The risk of colon cancer in the average person goes up significantly at age 50. In fact, according to the Centers for Disease Control, more than 90 percent of colorectal cancers occur in people aged 50 and older. So we recommend a colonoscopy once every 10 years, starting at age 50. If you have precancerous polyps, then you will need to have a repeat colonoscopy sooner, perhaps in 3-5 years. Or if you are at higher risk of colorectal cancer, you will need to start screening earlier and/or screen more often. You are considered higher risk if you have one of the following:
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A family history of colorectal cancer
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A hereditary syndrome, like familial adenomatous polyposis or Lynch syndrome
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Ulcerative colitis or Crohn's disease
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A personal history of adenomatous polyps
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Previous abdominal radiation (for example, adult survivors of childhood cancer or men treated for prostate cancer who received abdominal radiation therapy).
If you have one of these higher-risk conditions, be sure to check with your primary care provider to find out when you need to start screening for colorectal cancer and if genetic testing would be beneficial.
If you are 50 or older, or in one of the higher-risk groups, please give your family practice provider or internist a call today to see whether you need to be screened for colorectal cancer. Your well-being is in your hands, and timing is key with colorectal cancer prevention – don't wait until it's too late!
