Primary Central Nervous System (CNS) Lymphoma

Primary CNS lymphoma is a rare cancer that affects your central nervous system. It can form in your brain, spinal cord, the fluid around them, or behind your eye. It belongs to a group of cancers called non-Hodgkin lymphoma, which start in white blood cells. Though uncommon, this cancer can spread quickly within your central nervous system.

Types & Stages

There are two main types:

• Primary CNS lymphoma. Starts within the nervous system and stays in the brain, spine, spinal fluid or eyes. Most cases are a type called diffuse large B-cell lymphoma.
   
• Secondary CNS lymphoma. Begins somewhere else in the body and later spreads to the nervous system. More aggressive lymphomas are more likely to spread this way.

Signs & Symptoms

Your symptoms depend on where the tumor sits. Some tumors cause no symptoms, while others affect vision, movement or thinking. Common signs include:

• Nausea and vomiting
• Weakness in your arms, legs or face
• Headaches or confusion (signs of pressure in the brain)
• Vision problems, such as blurry or double vision
• Memory loss or trouble speaking
• Hearing loss or difficulty swallowing
• Seizures
• Loss of bowel or bladder control

Diagnosis

Your care team may use several tests to confirm a diagnosis:

• Physical and neurological exams to check your brain, spinal cord, and eyes.
   
• Imaging tests such as an MRI, CT, or PET scan to find the cancer.
   
• Blood tests to look for signs of cancer in your cells.
   
• Tissue and fluid tests that sample spinal fluid, bone marrow, or the tumor itself.

Treatment 

Treatment depends on your needs and may include:

• Chemotherapy, often using high doses of a drug called methotrexate.
   
• Radiation, such as whole-brain radiation to ease symptoms.
   
• Targeted therapy that uses proteins or antibodies to attack cancer cells.
   
• Stem cell transplant to replace blood cells damaged by treatment.
   
• Clinical trials that test new drugs and combinations.

Causes & Risk Factors

A weakened immune system is the main risk factor. This includes:

• HIV/AIDS, especially with an active Epstein-Barr infection
   
• Inherited immune disorders, such as Wiskott-Aldrich syndrome or common variable immunodeficiency
   
• Taking immune-suppressing drugs after an organ transplant

Screening

There is no routine screening for CNS lymphoma. Diagnosis depends on recognizing symptoms early and getting a prompt medical exam.