Familial tumours of the nervous system

Why have I been given this information?

You may have been given this information sheet by your Cambridge University Hospitals (CUH) treating team because you have a history of benign tumours in yourself and/or your family. These tumours may be related to a genetic condition. You are therefore being offered tests and advice to investigate the possibility that your diagnosis could be connected to a gene variant in one or more of your genes. This variant may also be called an 'alteration' or 'mutation'.

You will have the opportunity to discuss this fully with one of our team. This discussion may be with a consultant clinical geneticist, a genetic counsellor or a clinical nurse specialist. You may receive a separate appointment for this.

Tumours of the nervous system

How often are these tumours genetic?

Tumours of the nervous system, such as a meningioma or schwannoma, are not common conditions, but where they do occur, they are often treated at CUH. Meningiomas are the most common type of benign brain tumour. Schwannomas are rarer but are the most common tumour of the peripheral nerves. The peripheral nervous system is the network of nerves that lies outside of the central nervous system. The central nervous system is made up of your brain and spinal cord.

In most cases, we do not know what has caused the tumour to grow. Only a small number of these tumours are due to an existing, known genetic condition (called a tumour predisposition syndrome). Some factors that suggest a genetic cause are:

• developing tumours at a young age
• having multiple benign tumours
• several relatives on one side of the family having benign tumours of the same type
• occasionally people may have other features such as in their eyes or skin, or on other nerves in their body that suggest there might be a genetic cause for their tumour.

It is usually most appropriate to test someone who has the tumour or multiple tumours in a family first. If a genetic variant is found to be the cause, then relatives can be offered a test to clarify their risks and guide screening.

What genes are tested?

Several genes have been identified as associated with the development of tumours of the nervous system. Your clinician can provide further information on the specific genes included in your test if you wish to know this

What type of results might I get?

You should be aware that this type of test may identify a variant in a gene that could be responsible for your tumour(s); however, it is possible that it may not identify any gene variants at all. It can also identify one or more genetic variants that we cannot interpret at this time with current medical and clinical knowledge. We call these ‘variants of uncertain significance’ (VUS). We do not use this type of result to predict risk in your family members.

Tumour predisposition conditions

If the test results show that you have a gene variant that makes it more likely that you will have further benign tumours, we will discuss future monitoring and medical actions with you. You will be given advice about this by your genetic counsellor, doctor or specialist nurse.

What is involved?

The genetic test involves having a blood test. Your DNA is extracted from the blood sample for detailed analysis. As there are many genes to be examined, so initial results can take several months. If a variant is identified that is linked to tumour predisposition syndromes, other family members can be offered testing for the identified specific variant. This is quicker and normally takes four to six weeks. You will be asked to complete a consent form prior to having the test.

MyChart

We would encourage you to sign up for MyChart (opens in a new tab). This is the electronic patient portal at CUH that enables patients to securely access parts of their health record held within the hospital’s electronic patient record system (Epic). It is available via your home computer or mobile device. Please visit the MyChart information page for more information.

Contacts/further information

Your genetic counsellor, specialist nurse or doctor will be happy to address any questions you have. If you are not sure who to contact, please contact the NF2 PA on 01223 805128 or contact your team through MyChart.