What is primary CNS lymphoma

Primary CNS lymphoma (PCNSL) is a rare type of lymphoma which starts in the central nervous system (CNS).

PCNSL may affect one or several areas of the brain, spinal cord or eye (called intraocular lymphoma).

PCNSL usually affects a type of lymphocyte called B-lymphocytes. The most common type of PCNSL is a fast-growing non-Hodgkin lymphoma called diffuse large B-cell lymphoma (DLBCL).

A lymphoma that starts in another part of the body but is also in the brain at diagnosis, or spreads there later, is called a secondary CNS lymphoma. It may be treated differently to PCNSL.

It is best to read this information with our general information about primary brain tumours and non-Hodgkin lymphoma (NHL).

Symptoms of primary CNS lymphoma

PCNSL may cause different symptoms, depending on:

  • where the tumour is in the brain or spinal cord
  • how slowly or quickly it grows.

Some possible symptoms include:

  • behaviour or personality changes – these are common in PCNSL but changes are often slight and may only be noticed by close family or friends
  • numbness, tingling or weakness – some people may have numbness or weakness on one side of the body, or tingling and weakness in the arms or legs.
  • changes in balance or movement – if your balance and co-ordination are affected, walking may be more difficult.
  • seizures (fits)
  • problems with vision – if the lymphoma starts in or near the eye.
  • headaches, vomiting and problems with your eyesight – sometimes the lymphoma can increase the pressure in the skull. This may happen because of swelling or blockages caused by the tumour.

We have more information about these and other symptoms of brain tumours.

Causes of primary CNS lymphoma

The causes of PCNSL are mostly unknown. Like other cancers, it is not infectious and cannot be passed on to other people.

People whose immune system is not working properly have a higher risk of developing PCNSL. This includes:

  • people with HIV (human immunodeficiency virus)
  • people taking drugs called immunosuppressants after an organ transplant or to treat autoimmune disease.

But most people diagnosed with PCNSL do not have immune system problems.

Diagnosis of primary CNS lymphoma

Tests for PCNSL usually include a brain MRI scan and a biopsy.

A biopsy is when the surgeon removes a piece of the tumour. Then they can examine it under a microscope to look for lymphoma cells. There are different ways to take a brain biopsy. Your surgeon will explain what to expect in your situation.

We have more information about diagnosing brain tumours.

Further tests for PCNSL

You may also have tests to check for signs of lymphoma in other parts of the body. These may include:

Your doctor will usually ask you if they can take a blood sample to check for HIV and other infections such as hepatitis B and C. When they know whether you have these infections, they can plan safer and more effective treatment for you.

Driving and PCNSL

You will not be allowed to drive from the time of your diagnosis until at least two years after your treatment has ended.

If you normally drive, this change can be upsetting and frustrating. But this is a legal requirement. It is important to follow the advice you are given.

If you live in England, Scotland or Wales, you must contact the Driver and Vehicle Licensing Agency (DVLA) to tell them about your illness. If you live in Northern Ireland, contact the Driver and Vehicle Agency (DVA).

Treatment for primary CNS lymphoma

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

This will usually include:

  • a lymphoma doctor (an oncologist or haematologist)
  • doctors who specialise in treating brain conditions (neurologists or neurosurgeons)
  • a specialist nurse.

Your doctor or cancer specialist or nurse will explain the different treatments and their side effects. They will also talk to you about things to consider when making treatment decisions.

Treatments for PCNSL might include:

  • Chemotherapy
    Chemotherapy is often the first treatment for PCNSL. It is often given with the targeted therapy drug rituximab. Methotrexate is the most common chemotherapy drug for PCNSL. It can be given along with the chemotherapy drugs cytarabine or thiotepa, or with both of these drugs. Some people have the chemotherapy drugs temozolomide and procarbazine along with methotrexate and rituximab.
  • Targeted therapy
    The targeted therapy drug rituximab is often used with chemotherapy to treat PCNSL.
  • Radiotherapy
    Radiotherapy uses high-energy rays to destroy cancer cells, while doing as little harm as possible to normal cells. Radiotherapy may be given after chemotherapy, or on its own if you are not well enough to have chemotherapy. For PCNSL, radiotherapy is usually used to treat the whole brain. When lymphoma starts in the eye, radiotherapy can sometimes be given directly to the eye.
  • Autologous stem cell transplant
    An autologous stem cell transplant is sometimes used to treat PCNSL. It is an intensive treatment, so it is not suitable for everyone.

You may have some treatments as part of a clinical trial.

Treating symptoms of PCNSL

PCNSL can increase the pressure in the skull or spine. For some people, this can cause symptoms that need treatment straight away. You may be given drugs called steroids to reduce any swelling around the lymphoma. These may also shrink the lymphoma for a time.

You usually start taking steroids after you have had a biopsy. Often you will only take them for a few weeks, and you may be able to stop after you start chemotherapy.

Rarely, surgery may be used to reduce the pressure.

If you have seizures caused by PCNSL, you may be given drugs called anti-convulsants to help prevent them.

HIV treatment and PCNSL

People with HIV can usually have the same lymphoma treatment as people who do not have HIV. You will also have treatment to control your HIV. We have more information about treating HIV and lymphoma.

After primary CNS lymphoma treatment

At the end of your treatment, you will have a meeting with your lymphoma doctor or specialist nurse. They will explain how often you will have follow-up appointments and any possible late effects of treatment. They will also make you aware of possible signs of the lymphoma returning that you should be aware of.

Recovering after treatment for a brain tumour

After treatment for a brain tumour, it may take some time before your symptoms improve. You may have ongoing side effects or be adjusting to some physical or emotional changes caused by the brain tumour. Your healthcare team includes different professionals who can help as you recover.

Well-being and recovery

Even if you already have a healthy lifestyle, you may choose to make some positive lifestyle changes after treatment.

Making small changes such as eating well and keeping active can improve your health and wellbeing and help your body recover.

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