Can cancer be inherited?
- Cancer is considered a common condition and is diagnosed in 1 of 3 people within their lifetime.
- Cancer generally occurs sporadically (random / as a once off) because of environmental and lifestyle factors.
- Some cancers (about 10% of cases) occur because cancer ‘runs’ in the family (is inherited).
- Knowing your risk of hereditary cancer is important for
your future health as it allows access to appropriate testing,
screening and preventative measures.
When is a cancer hereditary?
- Hereditary cancer (also known as hereditary cancer syndrome) is an inherited condition which results in a greater risk to develop cancer compared to that of an average person.
- If your family has a hereditary cancer you have an increased
chance to develop cancer at an earlier than expected age.
What is the role of genetics in cancer?
All cancers are due to faults (mutations) in genes but most of these mutations are not inherited.
- Your body is made up of many cells and each one contains a copy of your genetic material that is made up of genes.
- Genes carry the information that defines how your body works, looks and develops.
- You have two copies of every gene as you inherit one from each parent.
- The role of some of your genes is to prevent the development of cancer.
- Faults in these genes cause hereditary cancer.
- If you have (or carry) a fault in these genes then you will have an increased risk - greater than that of the general population- to develop cancer in your lifetime.
How is hereditary cancer inherited?
- For most types of hereditary cancer syndrome the pattern of inheritance (or pattern of passing the gene fault from one relative to another) is autosomal dominant.
- This means that hereditary cancer occurs equally in males and females.
- The chance of a child inheriting this from a parent is 50/50.
How to look at your family history to assess your risk for hereditary cancer?
- If your family has many members (from the same or many generations) diagnosed with cancer (the same or associated) at a young age, and within the same family line, eg. ‘mother’s-side of the family’, then your family may be at risk for hereditary cancer.
- Not all families with hereditary cancer have a family history of cancer making it important to discuss this with your genetic counsellor Contact Us.
What are common examples of hereditary cancers?
- Breast and ovarian cancers.
- Colorectal cancers (Lynch syndrome and familial adenomatous polyposis (FAP)).
- Less well-known ones are; Cowden syndrome, Hereditary Diffuse Gastric Cancers, Peutz-Jeghers, Juvenile Polyposis Syndrome, Li-Fraumeni and von Hippel-Lindau disease.
When should you be concerned about hereditary cancer?
- You have at least one family member who had cancer diagnosed at an early age, in at least one family member e.g. under the age of 50 years.
- You have a family history of the same cancer such as breast, ovarian, colon, prostate cancers.
- You have a family history of related cancers e.g. breast and ovarian cancer.
- You have two or more relatives with rare cancers.
- Multiple primary (first) cancers in the same individual – same or different organs.
- Bilateral (both sides) cancers in paired organs e.g. breasts, eyes.
- Tumours associated with other genetic conditions or birth defects.
How will genetic counselling help you if you are concerned about hereditary cancer?
- You will be given information on the role of genetics in the development of cancer.
- A cancer risk model will be used to assess the risk of a hereditary cancer in your family.
- Depending on your risk, you will be given information on the benefits and limitations of options such as genetic testing, preventative management and screening.
- You will be given emotional support to help you cope and come to terms with your risk.
- You will have information and support from your counsellor to make medical and personal decisions for your future.
What happens during a genetic counselling session?
During genetic counselling the genetic counsellor will:
- Obtain a family and personal medical history.
- Draw up a family tree.
- Use your medical information and family tree to assess the risk of a hereditary cancer syndrome.
- Discuss the cause, inheritance, your risk of a hereditary cancer and the likelihood of cancer in you and other of your family members.
- Discuss genetic testing (if appropriate), preventative and screening options, including their benefits, risks and limitations.
Need more information about hereditary cancer?
Please Contact Us should you need more information about hereditary cancer, explore your risk for hereditary cancer or make an appointment to determine whether your family is at risk for hereditary cancer.
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