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Having a cousin or grandparent with colon cancer increases your risk


By Steven ReinbergHealth Day reporter

WEDNESDAY September 15, 2021 (HealthDay News) – Colon cancer risk exists in families, and it’s not just a parent or sibling who has had the disease that you should be concerned about.

If you have a second or third degree relative who had colon cancer at an early age, your chances of having the disease increase dramatically, according to a new study.

First-degree parents include parents, children, and siblings. Second degree parents include aunts, uncles, grandparents, grandchildren, nieces and nephews. Third-degree parents include first cousins, great-grandparents, and great-grandchildren.

“Our study provides new information on the magnitude of the risk for relatives further away from colorectal cancer cases, and in particular, for parents of cases diagnosed before the age of 50,” said researcher Heather Ochs- Balcom, Associate Professor of Epidemiology and the Environment. health care with the School of Public Health and Health Professions at the University of Buffalo (NY).

“This work is important given the increasing rates of early-onset colorectal cancer,” she said in a college press release. The researchers, at the University of Buffalo and the University of Utah, called early-onset colon cancer diagnosed before the age of 50.

First-degree relatives of someone diagnosed with early-onset colon cancer are six times more likely to develop colon cancer before the age of 50; Second-degree parents are three times more likely, and third-degree parents are about 1.5 times more likely, researchers say.

For the study, they looked at more than 1,500 cases of early-onset colon cancer in the Utah Cancer Registry.

The researchers also found that people have a 2.6 times higher risk of colon cancer at any age if they have a first-degree relative with early-stage colon cancer. And the risk is about twice as high for second-degree parents and 1.3 times as high for third-degree parents.

These results suggest that colonoscopy screening before the age of 50 may be beneficial for second-degree and possibly third-degree relatives of someone who has developed colon cancer, and not just for immediate family members.

The report was published in August in the journal Cancer epidemiology.

More information

To learn more about colon cancer, see the American Cancer Society.

SOURCE: University of Buffalo, press release, September 13, 2021

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