QUESTION: What are the risk factors of colon or rectal cancer, and when should I get screened?
ANSWER: Lifestyle, environment and your genetics all play a role in your chances of getting colon or rectal cancer, according to Robert Madoff, MD, a colon and rectal cancer specialist and the chief of the Colon and Rectal Surgery Division at the University of Minnesota Medical Center.
Heavy drinkers, diabetics, those who are inactive and the morbidly obese are at a higher risk of developing this particular type of cancer, Madoff said. A diet high in red meat and grilled or fried meat can also increase your chances of developing colon or rectal cancer.
But the single most significant factor in your colon or rectal cancer risk is something you can’t control: Your genes. Your chances of developing these types of cancers climb dramatically if you have an immediate family member who was diagnosed with colon or rectal cancer, Madoff said. Certain ethnic groups, like African Americans and Ashkenazi Jews, are also statistically more likely to develop colon or rectal cancer, simply because of hereditary factors.
For a smaller group of people with one of two gene mutations, however, the risk is all but unavoidable.
People with Familial Adenomatous Polyposis (FAP)—a rare genetic mutation that causes them to develop hundreds or thousands of polyps in their colons and rectums—have a 100 percent chance of developing the cancer over the course of their lifetimes, Madoff said. Those with Lynch syndrome—a mutation that also causes polyp growth—have an 80 percent chance of colon or rectal cancer over their lifetimes, Madoff said. Women with Lynch syndrome also have a higher risk of uterine cancer as well.
The average person without any hereditary risk should start colon and rectal cancer screenings at age 50, Madoff said, but those with a genetic risk need to start sooner. People who have an immediate relative with the cancer need to start the screenings 10 years before the youngest diagnosis age in their family. For example, a person with a family member who was diagnosed with colon or rectal cancer at age 35 should begin screenings at 25.
But those with the FAP or Lynch syndrome mutations—or an extensive family history of colon or rectal cancer—should consider the advantages of a cancer risk management program. The University of Minnesota Health Cancer Risk Management Program works with people to develop an individualized plan to manage their cancer risk.
“The first thing is to know your family history,” Madoff said. “If there’s a lot of people in your family who have had colon cancer or multiple polyps, then it’s important to talk with your doctor.”