Getting your genetic test results

Gene changes

A gene change or mutation is a permanent change in the DNA that makes up a gene. This can be inherited from a parent.

Changes to your genes can also happen during your lifetime. For example too much ultraviolet (UV) radiation from the sun can damage DNA in your skin cells and cause skin cancer. This is an environmental factor.

Doctors also call gene changes other terms such as gene:

• alterations

• variants

• faults

Genetic testing can tell you whether you have an inherited gene change that increases your risk of developing cancer.

What if the test doesn’t find a gene change?

A negative test result means that you are not carrying the gene they were looking for. This doesn’t mean that you definitely won’t get cancer. Your risk is likely to be similar to everyone else. You can still reduce your risk by choosing a healthy lifestyle.

Find out more about causes of cancer and reducing your risk

You could still be at high risk of particular cancers even if you have a negative result. Genetic testing usually only looks for faults in the known high risk genes. The uncertainty of this can be very difficult to deal with. Your genetics counsellor will advise and support you.

What if the test does find a gene change?

A positive test result means that you are carrying the gene change. This doesn’t mean that you have or will definitely develop cancer. But your risk is higher than the general population.

It can be difficult to find out that you have an increased risk of developing cancer. Most people who have a positive result will feel a range of emotions such as:

• resentment

• anger

• worry

• anxiety

This is understandable. Some people find that it helps to talk to their family members about their feelings. Other people may prefer to talk to a counsellor.

You can talk to your doctor or genetic counsellor to find out how much your risk of cancer is increased. They can tell you what check ups you need and how often you will need to have them. It is important to remember that not everyone who has a gene change goes on to develop cancer.

Whatever your situation, you can help to reduce your risk by choosing a healthy lifestyle.

Get more information on reducing your risk of cancer

Telling your relatives

You may be worried about which family members to tell and how to tell them. Your genetic counsellor can help you work out the best way to do this. Some clinics have prepared letters that you can send out to relatives but you may prefer to tell people face to face. Or you might want to do a mix of both, depending on which relative it is and your relationship with them.

Your relatives’ reactions may vary. It may be a shock to them if they hadn’t thought about having a family history of cancer. Some people may choose to ignore the result and may even find it difficult to talk to you afterwards. Others will be glad that you have warned them about the possibility that they may have a faulty gene and will then want to have a test themselves.

You might get test results at the same time as other family members. This can be very hard to cope with. You might feel guilty if you do not have a gene change, but your relatives do. You might also be trying to cope with their results.

Talking together as a family might be helpful. You can talk together at the genetic clinic, or with a counsellor. You could also try individual counselling. You can go back again if you don’t want counselling straight away.

Your options if you have an increased risk of cancer

Depending on the type of gene change and the types of cancer you are at risk of developing, your doctor might recommend:

• regular screening (also known as surveillance)

• treatments such as surgery or medicines

Regular screening to detect cancer early

Screening aims to spot cancers at an early stage when treatment is more likely to be successful. It can also help prevent cancer from developing by looking for changes that could lead to cancer.

The type of screening you have, when it starts, and how often you have it will depend on the type of cancer you are at risk of getting.

We have more information about screening for people at high risk of particular cancers:

• bowel cancer

• breast cancer

• womb cancer

• prostate cancer

• kidney cancer

Treatment to reduce your risk of developing cancer

You may be able to have treatment to reduce your risk of getting cancer. This might include surgery or medicines to reduce cancer risk. This is possible for some types of cancer where there is a known gene change.

When you have risk reducing treatments depends on the type of cancer you are at risk of developing, and the type of gene change. For some cancers, your risk may not be significantly increased until you are in your 30's or 40's. For other types of cancer, you might need treatment earlier.

Surgery to reduce cancer risk

You might be offered surgery to remove part of the body at risk of developing cancer. Risk reducing surgery doesn’t necessarily stop you from getting cancer completely. Nobody can guarantee that. But it will significantly reduce your risk of getting a particular type of cancer.

Surgery can change how you feel about yourself. For some people, knowing that they have reduced their risk makes them feel more confident and happier. For others, the changes in their body, whether visible or not, are very difficult to cope with. It is important to try to think about how you will feel if you do have treatment and how you may feel if you don’t.

Talk to your genetics specialist about the risks and benefits of having risk reducing surgery.

Breast or ovarian cancer

Women who have a high risk of developing breast or ovarian cancer may choose to have risk reducing surgery. To reduce the risk of breast cancer you may choose have both breasts removed (bilateral or double mastectomy). You may be able to have breast reconstruction at the same time as you have your breast removed or at a later date.

Find out about having a breast reconstruction

This is called preventive mastectomy, risk reducing breast surgery, or prophylactic mastectomy.

You may also choose to have your ovaries and fallopian tubes removed. This surgery is called prophylactic salpingo-oophorectomy or risk reducing ovarian surgery.

Womb cancer

People with Lynch syndrome have an increased risk of developing womb cancer. Your doctor may suggest an operation to remove your womb. This is called a hysterectomy. This is also known as risk reducing hysterectomy (RRH). Your team don't usually recommend this before you are 35 or 40 years old.

Bowel cancer

You may be able to have an operation to remove your large bowel to reduce your risk of bowel cancer. This is called prophylactic colectomy.

Thyroid cancer

Your doctor may suggest you have surgery to remove your thyroid if you have inherited a gene change. This is called prophylactic thyroidectomy.

Stomach cancer

Your doctor might suggest you have surgery to remove your stomach (total gastrectomy). This is also called a prophylactic total gastrectomy. You might have this if you have hereditary diffuse gastric cancer syndrome.

Medicines to reduce cancer risk

For some cancers you may be able to take medicines to reduce your risk instead of having surgery. This is commonly called chemoprevention. This is not chemotherapy.

If you have an increased risk of developing breast cancer doctors may offer hormone (endocrine) therapies to reduce your risk. Your team may call this treatment risk reducing endocrine therapy instead of chemoprevention.

But they mean the same thing. The type of hormone therapy you might have depends on your individual situation.

This is an overview of the types of hormone therapy you might have and when:

• tamoxifen if you are pre menopausal

• anastrozole if you are post menopausal

• raloxifene or tamoxifen if you are post menopausal and you can't take anastrozole

Find out about reducing your risk of breast cancer

People diagnosed with Lynch syndrome can take aspirin to reduce the risk of developing cancer.

Deciding whether to have risk reducing treatment

Choosing to have treatment to reduce your risk of cancer is a very personal decision. Before you decide to have any treatment to reduce your risk, it is worth thinking about the following questions.

• What treatment options are available to you?

• How much will treatment reduce your risk of developing cancer?

• How do you feel about having treatment?

• What does the treatment involve?

• What are the immediate and long term side effects of treatment?

• Can side effects be controlled?

• When should you have treatment?

• Will the treatment affect your fertility?

• Can you time your preventative treatment so that you can have a family first?

Finding out that you have a gene change may make you think about the choices you make in your life. For example:

• you may decide to have children earlier than you had planned, before having your ovaries removed

• you may want to have tests before pregnancy to avoid passing on a gene change

• it may affect the choices you make about work and your career

Your genetic counsellor or specialist nurse can talk through your options and help you decide what is right for you.