March is National Colorectal Cancer Awareness month

Colon cancer is one of the most common types of cancer. Photo credit James Meierotto.

Colorectal cancer is now the third most common cancer in the United States, and March is an ideal time to evaluate your risk. Understanding the basics of colorectal cancer and risk factors associated with the disease is the first step toward prevention.

Jeremy Cravens, MD, colorectal surgeon with AdventHealth Shawnee Mission, offered some insight about colorectal cancer including risks, screening and prevention.

What causes colon cancer?

Colon and rectal cancers begin as an overgrowth of the cells on the inner lining of these organs. Early areas of this overgrowth often form small tumors called polyps. While some of these polyps may remain benign, certain types have potential to become a cancer. While the specific cause of colon cancer in any individual is usually very difficult to know, we do know that a complex combination of genetic and environmental factors can contribute to the changes in these cells.

What are the risk factors of colon cancer?
For most people, a family history of colon cancer or precancerous polyps is the biggest risk factor. Other risk factors are lifestyle-oriented, including obesity, alcohol and tobacco use, consumption of processed meat and lack of physical activity. Risk levels increase as we age, most significantly between the ages of 40 and 50.

When should I get screened?

The general population should start regular screenings at age 45. Patients with a family history of colon cancer should start screening earlier – 10 years before the age that their affected family member was diagnosed with cancer. These patients should also undergo screening colonoscopy every five years as opposed to every 10 years. Talk with your primary care provider about when to begin screening, which test(s) to get, and how often to get screened, especially if you fall into one of these categories:

  • A close relative has had colorectal polyps or colorectal cancer
  • You have an inflammatory bowel disease like Crohn’s or ulcerative colitis
  • You have a genetic syndrome known to increase your risk for the disease.

What are the symptoms of colon cancer?
Without proper screening, colon cancer can largely go undetected—in many cases there aren’t any noticeable symptoms associated with the disease. However, if you have significant change in bowel habits, blood in your stool, dark stools or unexplained weight loss, you should call your doctor.

How is colon cancer detected?
There are many ways to detect colon cancer, from laboratory tests of the stool, to X-ray tests, to colonoscopies. Your age and possible symptoms will help determine which test is right for you. Of all the tests, a colonoscopy is the best way to make a definitive diagnosis.

How can colon cancer be prevented?

Aside from avoiding lifestyle behaviors that increase your risk, catching pre-cancerous tissue such as polyps early is the best way to prevent development of colon cancer. A polyp can take 10 to15 years to develop into cancer, so there’s lots of opportunity through regular screening to find and remove polyps before they turn into cancer.
Being better informed about colorectal cancer can help you take better control of your health. Maintaining healthy eating and exercise habits can help prevent colon cancer. Drinking in moderation and refraining from smoking are also helpful preventive approaches.

About AdventHealth Cancer Care

AdventHealth is Kansas City’s only affiliate of MD Anderson Cancer Center Network®, a program supported by MD Anderson Cancer Center. Learn more about AdventHealth Cancer Center Shawnee Mission at