Doctors often refer to it as hereditary nonpolyposis colorectal cancer or HNPCC. But you may have heard it’s more common name: Lynch Syndrome.
“About 15% of colorectal cancer is genetically inheritable and a smaller sub-set of that what we call Lynch Syndrome or HNPCC,” says Dr. Valerie Dyke. She is a colorectal surgeon on medical staff of Lee Memorial Health System. “We’ll see 50% of people by the time they’re aged 50 start to have cancer in their polyps if they have that type of genetic variant.”
The lifetime risk of colorectal cancer is 80% (for people with Lynch Syndrome). People with Lynch also have an increased risk of cancers of the stomach, small intestine, liver, gallbladder, urinary tract, brain, and skin. Women with this disorder have a high risk of ovarian and endometrial cancer. It’s why doctors are taking a proactive approach.
“We have a new program called reflex testing where every single colon tumor is going to be tested if it is removed in someone who is aged 60 or younger,” says Dr. Dyke. “We’ll test the tumor and see whether it has this genetic variant and if it does then there are blood tests they can run on other members of your family.”
In general colorectal cancers have few early warning signs. But a red flag for Lynch Syndrome is age. The average age for colorectal cancer patients is 72 years old- compared with Lynch patients who are diagnosed on average by 45. Many cases strike much younger.
Families with one or more cancer cases diagnosed under age 50 may want genetic counseling. Usually not found out of research or academic medical centers, testing is available at the Regional Cancer Center.
“It looks at actually genetic mismatches and specific chromosomes when they look at the blood. They look for abnormalities,” says genetic counselor Mary Ann Orlang.
Early detection is extremely important because Lynch-linked colorectal cancers are more aggressive.
“We think in average people it takes from 5-10 years to go from a polyp to a cancer. We think in people with HNPCC that they could go more rapidly, within a few years,” says Dr. Dyke.
Learning the low down on Lynch may lead to lowering your cancer risk.