Colorectal cancer can strike anybody. But the risk is greater for those with a family history of the disease. That’s one reason Boston Bruins President and Hockey Hall of Fame member Cam Neely gets a colonoscopy every three years — his mother died of the disease at the young age of 47.
“I learned that this type of cancer can be hereditary but if detected early is very treatable,” said Neely, president of the Cam Neely Foundation for Cancer Care. Earlier this year, Neely opened the Marlene Neely Center for Digestive Health, a comprehensive, state-of-the-art facility focused on the prevention, diagnosis and treatment of gastrointestinal illness. It is located at Tufts Medical Center in Boston.
Members of the general public are urged to have a colonoscopy starting at age 50 and every 10 years after that. Those in whom polyps are found are recommended to have a repeat test every three to five years, depending on the type and/or number of polyps found. Polyps are small growths on the lining of the colon or rectum that in some cases are deemed to be precancerous. Polyps are removed if found during a colonoscopy.
For those with a first degree relative with the disease, colonoscopies should begin at age 40, or 10 years before the relative’s age of diagnosis, said Jatin Roper, MD, gastroenterologist and Director for the Center for Hereditary Gastrointestinal Cancer at Tufts Medical Center. Most of these patients don’t have to return for another five years, though some with more concerning types of polyps should come back every three years, he said.
Dr. Roper said that approximately one-third of colorectal cancers are thought to have a familial link. Most of these cancers have not been linked to a genetic mutation. About 2 to 5 percent are caused by a defined, known genetic mutation.
If you have a first degree relative who has or had the disease — that’s a mother, father, sister or brother — your risk of getting colon cancer increases two to three-fold. The lifetime risk of getting the disease for the general public is about 4.5 percent, according to the American Cancer Society. So those with a first degree relative with the disease would have about a 9 percent or higher risk of getting the disease in their lifetimes.
Those with family histories of colorectal cancer or other cancers may be urged to undergo genetic testing designed to identify if they are families that pass on susceptibility genes from one generation to another, Dr. Roper said. Once very expensive, “the cost has dramatically decreased,” he explained. “We can identify a lot of patients that were not identified in the past.”
Patients identified by these tests may be watched more closely or even have their colons removed to prevent cancer, in some cases. They also can alert other family members to get tested for their genetic susceptibility.
There are two major subtypes of hereditary colon cancer — familial adenomatous polyposis (FAP) and Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC). Lynch syndrome is the most common. There are also some rare conditions that have been associated with an inherited risk for colorectal cancer. These include attenuated familial adenomatous polyposis (AFAP) and MUTYH-associated polyposis (MAP).
In some families, there is a strong history of colorectal cancer, although no known mutations have been detected. Familial or not, colorectal cancer can be prevented by early detection through the colonoscopy test.
The test is performed under conscious sedation and is not painful. “I highly recommend screenings be a priority if there is any family history or when you reach the recommended age,” said Neely. “The screening process is not uncomfortable and is relatively quick.”
There are alternatives to colonoscopy that may be available to some patients, particularly those who cannot tolerate a colonoscopy or who particularly dislike the preparation for the test. One option is a stool test that checks for blood. Another is a capsule the that is swallowed and scans the inside of the colon over a two to three-day period with precisely timed X-rays.
The downside of these is that they are not quite as effective in spotting smaller polyps, Dr. Roper said. And if polyps are detected, the patient still must undergo a colonoscopy later to have the polyps removed.
The bottom line, according to Dr. Roper, is that “colon cancer, while very common, can be prevented. But once it spreads to the liver or other organs, it is a big problem. Most of those people die.”
About 150,000 cases of colorectal cancer are diagnosed each year in the United States, according to the American Cancer Society. The disease causes about 50,000 deaths per year. About 90 percent of patients diagnosed with early stage cases survive.
Posted March 2018
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