The importance of colon cancer screening
By Johnathon Markus M.D.
Colon cancer is the second leading cause of cancer-related deaths in the United States. Every year, approximately 135,000 people in the United States are diagnosed with colorectal cancer and over 50,000 people will die because of it. These numbers can be very scary, and in fact, you might know someone who has been diagnosed with colon cancer.
The majority of colon cancers develop from pre-malignant polyps, which if left alone, have an increased risk of turning into cancer. This process is clinically silent and typically has no symptoms until cancer is present. Once present, many patients will develop fatigue, weight loss, a change in their bowel habits, or start to see blood in their stool. At this point, the process is less likely to be curable.
Risk factors for colorectal cancer include but are not limited to a family history of colon cancer in either your parents or siblings, certain genetic disorders, a history of colon polyps, eating red meat, a high fat diet, a high calorie diet, smoking, alcohol use, obesity, and diabetes. In America, the average citizen has a 5% lifetime risk of developing colon cancer, but if you have a family history, that risk increases to 12% or higher. It should be noted that red meat more than doubles your risk of colon cancer. In our community, red meat is often a core component of every meal.
There are also protective factors that you can take to decrease your risk of colon cancer. Eating more fruits and vegetables, exercising, taking in an adequate amount of folate and fiber, and being compliant with your cholesterol medication will decrease your risk of colon cancer. In addition, quitting smoking, decreasing red meat consumption, and controlling your diabetes are all important and necessary to lowering the risk.
Fortunately, we now have effective screening tools, and the vast majority of colon cancer can be prevented. There are several different modalities currently in deployment to prevent colon cancer, but the most common one is the colonoscopy. The colonoscopy is a procedure where a flexible camera is inserted in to the rectum and advanced to the end of the colon to an area called the cecum. Once there, we slowly pull the camera back and look for polyps. Once polyps are identified, we remove them through the camera, collect the tissue, and send it to a pathologist, who then tells us what kind of polyps were removed. Based on the number of polyps, the size, microscopic analysis, and other risk factors we can then make recommendations of when to schedule the next colonoscopy. Depending on a person’s risk factors, this is typically 3, 5, or 10 years, with some exceptions.
As scary as that sounds, most endoscopy centers and hospitals (including mine) use medications such as propofol to keep you sedated during the procedure. Propofol has the distinct advantage of putting you to sleep very quickly once infused, and you rapidly start to wake up once the infusion is over. Your only restriction is to not drive or make any medical or legal decisions that day. If you are afraid of anesthesia or worried about the rare risks of perforation or bleeding, talk with your doctor as an un-sedated colonoscopy or other screening options are available.
I frequently tell my patients the hardest part of the colonoscopy is not the procedure itself, but rather the preparation involved. Indeed, those who have had a colonoscopy will tell you this is the part they dread the most. I frequently tell my patients to consider the prep as a bowel cleanse. Preps can range from 4 liters of fluid to as little as 72 oz of solution, but availability ranges due to cost and insurance coverage. I cannot stress enough that the preparation is the most important part of the whole process. You must follow your prep instructions exactly as written. Multiple studies have shown that prep quality is one of the most important factors that increase polyp detection rates.
Colon cancer rates have fallen over the past two decades and this can mostly be attributed to screening. Every patient should undergo screening colonoscopies at age 50. This number changes to 40 or 10 years before the youngest family member was diagnosed if there is a family history of colon cancer. For example, if a father was diagnosed with colon cancer at age 48, his children should start screening at age 38. I would also recommend that if you see blood in your stool, no matter what age, you should see a gastroenterologist. Finally, a non-invasive method of testing for polyps or colon cancer is a test called the Cologuard, which was FDA approved in 2016. This requires mailing in a stool sample that can then be analyzed for abnormal tissue, and if positive, a colonoscopy is recommended. This test is done on a yearly basis.
I hope you have found this information informative.