Primary central nervous system lymphoma (PCNSL)

What is primary central nervous system (CNS) lymphoma?

Primary central nervous system lymphoma is a type of non-Hodgkin lymphoma that develops in the brain, the spinal cord and the eyes. Lymphoma is cancer that starts in the lymph glands or other organs of the lymphatic system.

The lymphatic system is a system of thin tubes and lymph nodes that run throughout the body. Lymph nodes are bean shaped glands. The thin tubes are called lymph vessels or lymphatic vessels. A fluid called lymph circulates around the body in these vessels and flows through the lymph nodes.

Read more about the lymphatic system

The lymphatic system runs throughout your whole body. You can get lymphoma almost anywhere, including the brain and the spinal cord. Most primary central nervous system lymphomas start in the front part of the brain (the cerebrum). They can also start in the:

• spinal cord – lymphoma that starts in the spinal cord is called primary spinal lymphoma

• eyes – lymphoma that starts in the eyes is called primary intraocular lymphoma

• layers of tissue that surround the brain (leptomeninges) – lymphoma that starts here is called primary leptomeningeal lymphoma

Diffuse large B-cell lymphoma develops when the body makes abnormal B cells. These B cells are a type of immune cell that helps us fight infections.

Symptoms of primary CNS lymphoma

Symptoms of primary CNS lymphoma depend on where the lymphoma started. Symptoms can include:

• headaches

• changes in your eyesight, such as blurred vision

• feeling or being sick

• changes to your personality

• fits (seizures)

• difficulty walking and balancing

Find out more about the symptoms of brain tumours

How common is primary central nervous system lymphoma?

Primary central nervous system lymphoma is rare. Around 2 in every 100 primary brain or spinal cord tumours (around 2%) are lymphomas.

Tests

You have tests to diagnose a lymphoma of the brain or spinal cord. Your doctor checks the size of the tumour and its location. This helps your doctor plan your treatment.

You usually have several tests. Your nurse and doctor will give you more information about each test you have. They will explain why you need them and how you will have them. They will also talk about any possible side effects.

The tests you might have include:

• MRI scan or CT scan

• a biopsy- you might have a brain biopsy. Or you might have a sample of fluid taken from inside your eye to check for lymphoma in the eye

• a test to check for cancer cells in the fluid that surrounds the brain and the spinal cord (a lumbar puncture)

• eye test

• blood tests

• a physical examination, your doctor checks the lymph nodes in your body, including your neck, armpits, groin and tummy. They may also listen to your chest

• neurological examination, this includes asking you simple questions to test your memory. Your doctor also checks your balance and coordination

• PET-CT scan

• testicular ultrasound scan for males. This checks for lymphoma in the testicles

We have more information about the tests you might have to diagnose a brain tumour

Treatment for primary central nervous system lymphoma

Treatment for primary central nervous system (CNS) lymphoma is different from other brain tumours. Surgery isn’t usually a possible treatment. This is because it’s difficult to remove these tumours without causing severe side effects.

You usually have treatment in 2 stages.

Induction

This is the first stage of treatment. You have chemotherapy to treat the primary CNS lymphoma.

Consolidation

This is the second stage of treatment. It aims to treat any remaining cells left behind after induction. This helps to reduce the risk of the lymphoma from coming back.

Your doctor and specialist nurse will talk to you about your treatment. They will explain what it involves and any possible side effects. They will also tell you more about the specific treatment during induction and consolidation.

You can read about treatment for lymphoma of the eye on our treatment options for eye cancer page

Follow up

You have regular appointments with your doctor or nurse after treatment finishes. Your doctor examines you at each appointment. They ask how you are feeling, whether you have had any symptoms or side effects, and if you are worried about anything. You also have MRI scans on some visits.

How often you have check ups depends on your individual situation.

For a lymphoma of the brain or the spinal cord, you usually have an MRI scan every 3 to 4 months, for up to 2 years. The scans usually become less frequent after 2 years. Your doctor will let you know how often you have them.

Read more about follow up appointments after treatment for a brain tumour

Coping with lymphoma of the brain or spinal cord

Coping with a diagnosis of cancer can be difficult, both practically and emotionally. It can be especially difficult when you have a rare cancer. Being well informed about the type of cancer you have, and its treatment can make it easier to cope.  

Find out what you can do, who can help and how to cope with a brain tumour