Secondary CNS lymphoma happens when non-Hodgkin’s lymphoma spreads to the brain, spinal cord, or eyes. Its symptoms depend on the areas of the CNS that are affected. The outlook for people with this lymphoma is poor.

Secondary central nervous system (CNS) lymphoma is when non-Hodgkin’s lymphoma (NHL) spreads to the central nervous system (CNS). Overall secondary CNS lymphoma is rare, but when it does occur, it may be very serious.

Keep reading to learn more about secondary CNS lymphoma, including symptoms, diagnosis, and treatment.

Primary vs. secondary CNS lymphoma

CNS lymphoma can be either primary or secondary:

  • Primary CNS lymphoma: In primary CNS lymphoma, the lymphoma has originated in the CNS.
  • Secondary CNS lymphoma: In secondary CNS lymphoma, the lymphoma has spread to the CNS from another part of the body. When lymphoma spreads widely to other areas of the body, it’s called “systemic lymphoma.”

Between 2% and 10% of people with NHL have CNS involvement. Secondary CNS lymphoma happens when NHL that had started in another area of your body spreads to the CNS. Affected areas may include your brain, spinal cord, and eyes.

Secondary CNS lymphomas typically involve aggressive types of NHL. According to the Leukemia and Lymphoma Society, 90% of CNS lymphomas arise due to diffuse large B-cell lymphoma (DLBCL).

The remaining types of NHL related to CNS lymphoma include other aggressive types of NHL such as Burkitt’s lymphoma and lymphoblastic lymphoma, as well as some types of slow-growing (indolent) NHL.

If your condition has been diagnosed as NHL, your lymphoma treatment may include treatment to prevent it from spreading to your CNS. This treatment is called “CNS prophylaxis” and is used in people with aggressive NHL that are at a high risk of CNS involvement.

A 2018 study notes that secondary CNS lymphoma happens in less than 5% of aggressive NHLs and less than 1% of indolent NHLs when CNS prophylaxis is used.

Secondary CNS lymphoma can occur in up to 50% of some aggressive types of NHL when no CNS prophylaxis is given. Examples of such lymphomas include:

Is secondary CNS lymphoma curable?

Secondary CNS lymphoma typically can’t be cured. Instead, treatment for this type of lymphoma aims to manage your symptoms, stop the lymphoma from progressing further, and prolong survival.

CNS lymphoma can affect one or multiple areas of the CNS. Its symptoms depend on which part or parts of the CNS are affected.

Here are the different symptoms associated with each area of the CNS.

Secondary CNS lymphoma in the brain

When secondary CNS lymphoma affects the brain, it may cause:

Secondary CNS lymphoma in the spinal cord

If secondary CNS lymphoma is in the spinal cord, it may lead to symptoms like:

Secondary CNS lymphoma in the eye

The presence of secondary CNS lymphoma in the eye can cause symptoms such as:

Lymphoma may spread from its initial site through the lymphatic system or the bloodstream to other areas in the body, including the CNS.

Generally speaking, people with aggressive, more advanced types of NHL are at a higher risk of CNS involvement. Other risk factors may include:

  • older age
  • involvement of areas outside of the lymph nodes, particularly the:
    • upper part of the nose and throat (nasopharynx)
    • breasts
    • adrenal glands
    • kidneys
    • testes
    • bone marrow
  • high levels of lactate dehydrogenase (LDH) in your blood

Additionally, having a weakened immune system may increase your risk of secondary CNS lymphoma. Some causes of a weakened immune system that may increase your risk are:

In order to diagnose secondary CNS lymphoma, a doctor will first take your medical history and do both a physical and a neurological exam, during which they’ll check things like your mental state, coordination, and reflexes.

They’ll also order a variety of lab tests such as:

A visual exam is also important to diagnose secondary CNS lymphoma. The exam typically involves imaging and may also involve:

Sometimes a biopsy sample is needed, which can be analyzed in a lab to confirm a diagnosis of secondary CNS lymphoma as well as to further characterize the cancer. A biopsy is typically collected using a thin needle guided by imaging.

When secondary CNS lymphoma affecting the eye is suspected, a doctor may carefully collect a sample of vitreous fluid to analyze. The collection is done with a procedure called a “vitrectomy.”

There’s no standard treatment for secondary CNS lymphoma. Instead, the doctor will tailor a treatment plan to your individual situation. The broad goals of treatment are to:

  • manage your symptoms
  • slow the progression of your lymphoma
  • prolong survival

Some of the types of treatment that may be used for secondary CNS lymphoma, either alone or in combination, are:

The outlook for people with secondary CNS lymphoma is poor. There are several factors that can influence outlook, including:

  • the part or parts of the CNS that are affected
  • which other areas of the body are affected by lymphoma
  • the type of lymphoma that you have
  • how the lymphoma responds to the recommended treatment
  • your age and overall health

Overall survival time for secondary CNS lymphoma may vary. A 2021 study notes that older research has found that the median overall survival for secondary CNS lymphoma has ranged from 3.9 months to 1.5 years.

Secondary CNS lymphoma happens when NHL spreads to your CNS. While secondary CNS lymphoma isn’t common, it’s more likely to occur in people with advanced, aggressive types of NHL.

It’s possible for secondary CNS lymphoma to affect one or a combination of the brain, spinal cord, or eyes. The symptoms you experience depend on the areas of the CNS that are affected.

The outlook for people with secondary CNS lymphoma is typically poor, but each individual is different. Be sure to have an open conversation with a care team about your specific situation.