Colorectal cancer (cancer of the colon and rectum) continues to be the second leading cancer-causing death of both men and women in the U.S. It is, however, the third most common cancer diagnosed in our country. The only more common cancers in men are that of prostate and lung, and women are breast and lung. According to the most recent statistics of the CDC, 141,125 people were diagnosed with colorectal cancer in 2017 with 52,547 deaths. Of every 100,000 people, there are 37 diagnosed with colorectal cancer and 14 deaths.
Colorectal cancer begins in early stages as growths or polyps that develop in the large bowel. The most common polyps are adenomatous. These are not initially cancer by nature but are likely to turn into a cancer over time. There are also inflammatory, hyperplastic, and villous polyps ranging from minimal to significant risk of evolving into colon cancer. As cancer evolves, one may eventually have complaints of blood in the bowel movement, persisting abdominal pains or cramps, or unexplained weight loss. Although these symptoms are not exclusive to colon cancer, immediate medical help should be sought if these complaints are present. Early on, there may be absolutely no symptoms at all.
Although there are no absolute reasons that individuals develop colon cancer, there are some risk factors to consider. As we age, our probabilities increase. According to the CDC, more than 90% of cancers occur in those over fifty. As such, the general recommendations are that men and women begin routine screening at forty-five years old. There is an increased incidence for those with underlying inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease. If you have a family history (mother, father, sister, or brother) with a diagnosis of colon cancer discovered before age 50, or if you have a genetic syndrome such as familial adenomatous polyposis or hereditary non-polyposis colorectal cancer, you may have an increased risk and require screening earlier than the routine recommendation of 45 years old.
As March is Colorectal Cancer Awareness Month, your family physician can help you evaluate your risk and screening options and may provide preliminary testing in office. There are several screening tests. Most involve the evaluation of a stool specimen, such as the guaiac-based fecal occult blood test (gFOBT) which tests for the presence of blood, the fecal immunochemical test (FIT) that measures antibodies that indicate bleeding, and the FIT-DNA test, checking for altered DNA combined with the antibody test. Although a positive screening test is not an assurance of cancer, it is a marker for timely evaluation.
Colonoscopy is a procedure that checks for cancer in the rectum and entire colon. With the patient under sedation, a long, thin, flexible scope is used to painlessly visualize the bowel and remove polyps as well as biopsy areas of suspicion. This is also the procedure commonly used if any of the previous screening tests return as positive. Usually, this screening test is only needed once every ten years as opposed to annually for the less reliable gFOBT and FIT, or every three years for FIT-DNA, commonly marketed as Cologuard.
Additional techniques include capsule endoscopy (swallowing a camera in a pill) and virtual colonoscopy (a series CT radiology pictures combined to provide an image of the bowel). As relatively new procedures, they may not be covered by insurance or available in your area. Along with recommendations from your doctor, check with your insurance coverage to determine which tests may be choices for your screening evaluation.
Bradford Croft, DO
East Flagstaff Family Medicine, LTD