When cancer runs in a family

3 minute read time.

If several people in your family have had cancer, you may be worried that cancer runs in your family. Knowing that a grand-parent, a parent or an uncle, for example, have had a cancer experience can make you feel at risk of developing cancer too. Besides, regular mention of the BRCA genes or ‘cancer genes’ in the media may have led you to wonder about inherited cancers.

It’s important to know that inherited cancers remain rare. They represent 5% of cancers. Only certain types of cancer can be inherited. These include cancers of the bowel, breast, ovary and womb. This means that most cancers are not caused by inherited genes.

We talk about inherited cancers when people are born with a gene mutation that puts them at higher risk of getting cancer. That gene mutation has been passed on by one of the parents who also carries the mutated gene. If you inherit a gene mutation, it is in all your cells. This includes the sperm cells in men and the egg cells in women. This means there is a 50% chance of passing the gene mutation to any children you may have.

Inheriting a gene mutation does not mean you will definitely have cancer, but it means you are at a higher risk of developing certain types of cancer.

It is possible there is a cancer gene in your family if:

  • two or more close blood relatives on the same side of the family had the same type of cancer. Close relatives are a parent, uncle, aunt, grand-parent, brother, sister.
  • members of the family have had cancer at a young age (under 50)
  • certain combinations of cancers have occurred on the same side family (for example bowel and womb or breast and ovary)
  • you have a family history of cancer and are of Polish or of Ashkenazi Jewish descent.

If any of this applies, it’s a good idea to talk to your GP. Discussing your family history of cancer with your doctor will help them assess your risk. They will then be able to refer you to a specialist clinic where you’ll have genetics tests.

We have an online self-assessment tool that can help you find out if there’s a risk of cancer running in your family. You can use OPERA and answer a short series of questions to assess whether there may be an inherited gene mutation in your family.

 Select image to take you to OPERA

Our booklet Cancer genetics, how cancer sometimes run in families gives more detailed information about genes and inherited cancers. It explains how genetic testing is done and some of the issues around having it. In the booklet you’ll also find information about risk-reducing treatments and screening.

You may find our below video on genetic testing helpful. 

 

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