Primary central nervous system (CNS) lymphoma is a disease in which malignant (cancer) cells form in the lymph tissue of the brain and/or spinal cord.

Lymphoma is a disease in which malignant (cancer) cells form in the lymph system. The lymph system is part of the immune system and is made up of the lymph, lymph vessels, lymph nodes, spleen, thymus, tonsils, and bone marrow. Lymphocytes (carried in the lymph) travel in and out of the central nervous system (CNS). It is thought that some of these lymphocytes become malignant and cause lymphoma to form in the CNS. Primary CNS lymphoma can start in the brain, spinal cord, or meninges (the layers that form the outer covering of the brain). Because the eye is so close to the brain, primary CNS lymphoma can also start in the eye (called ocular lymphoma).

Enlarge

Anatomy of the lymph system, showing the lymph vessels and lymph organs including lymph nodes, tonsils, thymus, spleen, and bone marrow. Lymph (clear fluid) and lymphocytes travel through the lymph vessels and into the lymph nodes where the lymphocytes destroy harmful substances. The lymph enters the blood through a large vein near the heart.

Having a weakened immune system may increase the risk of developing primary CNS lymphoma.

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. People who think they may be at risk should discuss this with their doctor.

Primary CNS lymphoma may occur in patients who have acquired immunodeficiency syndrome (AIDS) or other disorders of the immune system or who have had a kidney transplant. For more information about lymphoma in patients with AIDS, see the PDQ summary on AIDS-Related Lymphoma Treatment.

Tests that examine the eyes, brain, and spinal cord are used to detect (find) and diagnose primary CNS lymphoma.

The following tests and procedures may be used:

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• Neurological exam: A series of questions and tests to check the brain, spinal cord, and nerve function. The exam checks a person’s mental status, coordination, ability to walk normally, and how well the muscles, senses, and reflexes work. This may also be called a neuro exam or a neurologic exam.
• Slit-lamp eye exam: An exam that uses a special microscope with a bright, narrow slit of light to check the outside and inside of the eye.
• Vitrectomy: Surgery to remove some or all of the vitreous humor (the gel-like fluid inside the eyeball). The fluid is removed through tiny incisions and then viewed under a microscope by a pathologist to check for cancer cells.
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography. For primary CNS lymphoma, a CT scan is done of the chest, abdomen, and pelvis (the part of the body between the hips).
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the brain and spinal cord. A substance called gadolinium is injected into the patient through a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Lumbar puncture: A procedure used to collect cerebrospinal fluid (the fluid in the spaces around the brain and spinal cord) from the spinal column. This is done by placing a needle into the spinal column. This procedure is also called an LP or spinal tap. Laboratory tests to diagnose primary CNS lymphoma may include checking the protein level in the cerebrospinal fluid.
  Enlarge
  

  Lumbar puncture. A patient lies in a curled position on a table. After a small area on the lower back is numbed, a spinal needle (a long, thin needle) is inserted into the lower part of the spinal column to remove cerebrospinal fluid (CSF, shown in blue). The fluid may be sent to a laboratory for testing.
• Stereotactic biopsy: A biopsy procedure that uses a computer and a 3-dimensional (3-D) scanning device to find a tumor site and guide the removal of tissue so it can be viewed under a microscope to check for signs of cancer.
• Complete blood count (CBC) with differential: A procedure in which a sample of blood is drawn and checked for the following:
  • The number of red blood cells and platelets.
  • The number and type of white blood cells.
  • The amount of hemoglobin (the protein that carries oxygen) in the red blood cells.
  • The portion of the blood sample made up of red blood cells.
  Enlarge
  

  Complete blood count (CBC). Blood is collected by inserting a needle into a vein and allowing the blood to flow into a tube. The blood sample is sent to the laboratory and the red blood cells, white blood cells, and platelets are counted. The CBC is used to test for, diagnose, and monitor many different conditions.
• Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) depends on the following:

• The patient's age and general health.
• The level of certain substances in the blood and cerebrospinal fluid (CSF).
• Where the tumor is in the central nervous system.
• Whether the patient has AIDS.

Treatment options depend on the following:

• The stage of the cancer.
• Where the tumor is in the central nervous system.
• The patient's age and general health.
• Whether the cancer has just been diagnosed or has recurred (come back).

Treatment of primary CNS lymphoma works best when the tumor has not spread outside the cerebrum (the largest part of the brain) and the patient is younger than 60 years, able to carry out most daily activities, and does not have AIDS or other diseases that weaken the immune system.