Notes on wording:

Breast cancer can affect anybody, and everybody is welcome in CoppaFeel!’s community. We’re actively inclusive in our language and we ask people how they want to be described. 

The word ‘chest’ is inclusive of all bodies and genders. When we need to be clinically accurate we use the word ‘breast’. You might prefer to call your chest something else, and that’s ok! 

Here is some information on changed genes which can run in families (genetic). Another word for this is inherited. 

For example, a person may have an inherited faulty gene. 

Key words explained:

Family history: 

Members of a family may have the same type of cancer. For example, a family history of breast cancer. When we talk about a family history of cancer, we focus on blood relatives, and it doesn’t mean everyone in the family will have cancer. 

Both mothers and fathers can inherit, carry and pass on a changed gene that increases the risk of breast cancer.  While a man (someone assigned male at birth) with a changed gene is less likely to develop breast cancer himself, he can pass the changed gene on to his children. When thinking about family history of breast cancer, it’s important to think about relatives on both the mother’s and father’s side of the family.

Faulty: 

Something is wrong, for example a faulty gene does not work in the right way. 

Inherited:

Passed on through genes in a family. 

Genes: 

Genes are a part of each cell in the body and are passed on from parents to children. They are the code for who we are. For example, your eye colour is based on your genes.

Carrier: A person with a changed gene is referred to as a carrier. Being a carrier does not necessarily mean that you will develop breast cancer, but it does put you at a higher risk compared to the general population.  

Genetic: Relating to genes. For example, genetic testing can show whether there is a fault in a gene. 

Genetic counsellor:  A genetic counsellor is a specialist who can help you to understand a genetic condition that runs in your family and options for genetic testing.

Other genetic conditions linked to breast cancer

Some genetic conditions caused by rare changed genes are also linked to breast cancer. We have talked about Peutz-Jegher syndrome and PTEN Hamartoma tumour syndrome above too.  

• Peutz-Jegher syndrome (changed STK11 gene)
• Cowden syndrome/PTEN hamartoma tumour syndrome (changed PTEN gene)
• Hereditary diffuse gastric (stomach) cancer syndrome (changed E-cadherin (CDH1) gene)
• Neurofibromatosis type 1 (changed NF1 gene)

Read more about these on this Cancer Research UK page.

Family history

Having a first degree relative (family member) diagnosed with breast cancer approximately doubles the risk of breast cancer. This could be a family member of any gender, and male relatives can be diagnosed with breast cancer too. 

This risk is higher when more close relatives have breast cancer, or if a relative developed breast cancer under the age of 50. Most people who have a close relative with breast cancer will never develop it.

There are guidelines in the UK to help GPs find people who might have an increased risk of breast cancer due to their family history. Source: CRUK  

GP referral to a genetics specialist 

Your GP may refer you to a specialist breast clinic or genetics clinic for assessment if you have any of the following:

• one first degree female relative or relative assigned female at birth diagnosed with breast cancer aged younger than 40 (a first degree relative is your parent, brother or sister, or your child)
• one first degree male relative or relative assigned male at birth diagnosed with breast cancer at any age
• one first degree relative with cancer in both breasts where the first cancer was diagnosed aged younger than 50
• two first degree relatives, or one first degree and one second degree relative, diagnosed with breast cancer at any age (second degree relatives are aunts, uncles, nephews, nieces, grandparents, and grandchildren)
• one first degree or second degree relative diagnosed with breast cancer at any age and one first degree or second degree relative diagnosed with ovarian cancer at any age (one of these should be a first degree relative)
• three first degree or second degree relatives diagnosed with breast cancer at any age

Your GP may also refer you if you have one first degree or second degree relative diagnosed with breast cancer when they were older than 40 years and one of the following:

• the cancer was in both breasts (bilateral)
• the cancer was in a man
• ovarian cancer
• Jewish ancestry
• sarcoma (cancer of the bone or soft tissue) in a relative younger than age 45 years
• a type of brain tumour called glioma or childhood adrenal cortical carcinomas
• complicated patterns of multiple cancers diagnosed at a young age
• two or more relatives with breast cancer on your father’s side of the family

Genetic testing for breast cancer

If you are worried about a history of breast cancer in your family, talk to your GP. If your GP thinks you could have a changed gene, they can suggest you are offered testing The genetic test usually has 2 steps:

• Your relative with cancer has a blood test. This will check if they have a changed gene. It should take about 8-12 weeks to get a result for this test.
• If your relative is found to carry a changed gene, you can have a blood test at a genetic clinic. This will test to see if you have the same changed gene, and predict your risk of getting breast cancer.

If relatives who have had cancer are not available, you may be offered genetic testing if you have at least a 10% chance of having the gene change. This usually means you have a strong history of breast cancer at younger ages in your family.

The genetics specialists can work out your risk of getting breast cancer, and may suggest extra screening. 

You might start having screening from a younger age. Some people decide to have surgery to reduce their risk. You can talk about all of the different options with a genetic counsellor.

What if I’m at high risk of developing breast cancer?

If specialists have told you there is a moderate or high risk of developing breast cancer, you may be offered regular screening or surveillance, depending on your age. Surveillance means doctors check you more often than usual, to check for any changes.  

Screening aims to find breast cancer early, often before any symptoms appear. Early detection increases the chances of successful treatment.

The type of screening offered will depend on:

• Your age
• If you have had breast cancer
• Your level of genetic risk

For younger people, mammograms may not be offered due to dense breast tissue, which can make the images less clear. In these cases, MRI screenings may be recommended, and MRI and mammograms may be used depending on the specific risk and breast density.

If you would like to look into this further, your GP can refer you to the nearest genetics team for a CanRisk report. They will talk about your risk of breast cancer and arrange for screening and referrals to local NHS breast screening programmes.

Why do mammograms happen from age 50?

In most cases, the risks of screening women under 50 would outweigh the benefits. Women with a high risk of breast cancer can be screened at any age. However, low-risk women under 50 are not invited to be screened as part of the national screening programme. This is because x-rays expose you to a small amount of radiation. Any exposure to radiation can very slightly increase your risk of cancer. Read more on our page here.

How can I reduce my breast cancer risk? 

You can reduce your risk by not smoking and limiting alcohol. Live a healthy, active lifestyle and eat a balanced diet. 

Any amount of physical activity is good for you, and is better than none. The more you do, the better!

How can one twin have breast cancer and the other doesn’t?

Most cancers happen due to environment, lifestyle factors, and random chance rather than because of inherited risks. When someone carries a gene chance which increases their risk of cancer, this increases their chance of developing cancer in their lifetime but is not a guarantee. 

For that reason, identical twins who carry the same genetic change that increases their cancer risk may not both develop cancer. Also, not all twins are identical – fraternal twins share the same genetic make up as siblings born separately, so it is possible for one twin to be a carrier and the other not. 

What does risk reducing surgery mean?

Risk reducing surgery is an operation to remove healthy breast tissue from both breasts. It is also called a risk-reducing bilateral mastectomy.  

Although most of the breast tissue is removed, it is not possible to remove it all. There is still a small risk of breast cancer developing. 

This operation is only suitable for people who have a high risk of getting breast cancer. The specialists and surgeons will talk to the person about their options for reducing their risk.  

How can I find out about my family history of breast cancer?

If you are in contact with your family, it can be helpful to ask them about previous cancers in blood relatives to gather a family history. If you are due for an appointment in clinical genetics, your clinician will understand if you have limited or no contact with your blood relatives and cannot provide this information. This may limit their ability to provide an accurate risk assessment for you.

When would my breast cancer risk be worked out?

This depends on your individual clinical pathway. If you have had breast cancer yourself, your oncology team (cancer team) may be able to provide a breast cancer risk assessment for you. A risk assessment may also be provided by a clinical genetics service. Breast cancer risk assessment is often done using a tool called CanRisk.

Remember: 

Most breast cancers happen by chance. Researchers estimate that only around 5 to 10 out of 100 breast cancers (5 to 10%) are caused by a changed gene.