Colon cancer is the second leading cause of cancer death in the US. And although there is no single cause, one in 20 people will be diagnosed with this disease. Did you know that certain factors can push this risk even higher – up to 100%? Having these risk factors on your radar from a young age will allow you to be your own advocate and be proactive about your health and screenings. Find out what Dr. William E. Karnes of the University of California Irvine has to say.
The Subgroup Breakdown
William E. Karnes, MD
There are three subgroups of risk– sporadic, familial and hereditary. If you fall into the sporadic group, which means you have no family history of cancer or inherited genetic predisposition, you have a 3-7% lifetime risk of getting colon cancer. If you have familial risk, a single first degree family member (parent or sibling) with colon or endometrial cancer under age 50, your lifetime risk increases to 10-20%. Family history is an important indicator not only because of shared genes, but similar lifestyles too.
Those who have the highest lifetime risk of colon cancer are in the hereditary subgroup. Depending on the particular genetic syndrome, including Lynch, FAP, MAP, Peutz-Jegher’s and others, the chances of getting colon cancer may be 30-100%. If you have a family history, talk to your doctor!
Factors You Can’t Control
All colon cancers are caused by gene mutations. Your risk increases with age because new mutations accumulate as we get older, which is why the majority of colon cancers occur after age 50 (males slightly earlier than females.) African-American males tend to get colon cancer a bit earlier, and Asians and Hispanics a bit later. Certain inherited mutations can cause colon cancer to develop at much younger ages.
…And Those You Can
So what can you do? You can reduce your risk of colon cancer by limiting your intake of red and processed meat, staying lean, exercising, limiting alcohol consumption and by not smoking. You also reduce your risk by controlling and treating conditions like inflammatory bowel disease or type II diabetes.
Fortunately, most colon cancers are preventable through lifestyle changes and the removal of precancerous polyps through screening. Colonoscopy is the gold standard for finding polyps and the only test that allows for their removal. The best chance of preventing colon cancer, even for those with an inherited syndrome, is to follow the recommended guidelines for colonoscopy. No matter which risk subgroup you fall into, colonoscopy and removal of polyps can reduce your risk for colon cancer by an additional 70-90%!
William E. Karnes, MD
Director, High-risk Colon Cancer Program
H.H. Chao Comprehensive Digestive Disease Center
UC Irvine Health
Dr. Karnes is a fellowship-trained gastroenterologist who specializes in disorders of the gastrointestinal tract, with an emphasis on colon cancer screening and identifying patients and families with a genetic risk for developing the disease. He also conducts translational research on colon cancer prevention.
Take our colon cancer risk quiz, and don’t forget, the Colon Cancer Alliance serves as a source of information about colon health. If you have additional questions about colon cancer screening or are in need of support, please contact our free Helpline at (877) 422-2030. We’re here to help.