Genetic testing for women affected by ovarian cancer

We offer this test to people who have a common type of ovarian cancer.

The results can help your doctor plan the best treatment for you. They can also give you useful information about your future risk of cancer.

Because we share genes with our relatives, your results may also help them understand their own risk.

The test looks for changes in certain genes, mainly BRCA1 and BRCA2 genes. Changes in these genes can increase the risk of ovarian and breast cancer.

The test also looks for changes in other genes linked to:

• ovarian cancer
• womb (endometrial) cancer
• bowel cancer

The test consists of two parts:

1. Blood test (germline testing)

   This test looks at the genes you were born with. It involves taking a sample of your blood and sending it to a laboratory for analysis. You will need to give your consent to have this test. The results usually take up to 12 weeks.

   If a gene change is found, your relatives may also carry it. Please note that this applies to both men and women in your family.

2. Tumour test (somatic testing)

   This test looks at the genes in your cancer cells. It involves sending a sample of your tumour to a specialist laboratory for analysis. The sample is usually taken at the time of diagnosis or during surgery. The results usually take about five weeks.

   If a change is found only in the tumour and not in your blood, this has no impact on your relatives.

There are a few possible outcomes:

1. A gene change is found in both your blood and tumour

This result may help to guide your treatment options. It may also mean that you have a higher risk of developing another cancer.

Your relatives may also have a higher risk and they can choose to have a genetic test if they wish.

They may be offered:

• extra screening to find cancer early
• advice on ways to reduce their risk

If you have children, each child has 1 in 2 (50%) chance of inheriting the gene change.

2. A gene change is found in the tumour only

This means that:

• the change is only in the cancer cells
• we have not identified a genetic cause for your cancer
• your relatives do not have a higher risk of developing cancer

Your doctor will still use this information to plan your treatment.

3. An unclear result from the blood test

Sometimes the test finds a change that is difficult to interpret and we may not fully know what it means. This can feel uncertain. More information about your family history or additional tests may help to clarify the result.

If you have a family history of cancer, your relatives may still have an increased risk. If you are worried, talk to your GP or hospital doctor.

Your doctor will usually give you your results at your next appointment.

If a gene change is found in your blood, they will refer you to a genetic specialist.

The genetic specialist will:

• explain your results clearly
• discuss what they mean for you and your relatives
• support you in deciding what to do next

You will have a chance to ask questions and think about the best way forward.

It is your choice whether to have genetic testing.

If you decide not to go ahead:

• some new treatments may not be available to you
• your doctor will use standard test results to plan your treatment and care
• the genetics team will be unable to fully assess your family’s risk. This means that any advice for relatives would be based on family history alone.

If you would like more information or support, please speak to your hospital doctor.

Gynae-oncology department
University College Hospital Macmillan Cancer Centre
Huntley Street, London WC1E 6AG
Team PA telephone: 020 3447 8047 / 8025

The Macmillan Support and Information Service offers advice, support and information to anyone affected by cancer or a blood condition. You can drop in any time between 9am and 4.45pm, Monday to Friday, or call 020 3447 8663.