Questions About Cancer? 1-800-4-CANCER

Primary CNS Lymphoma Treatment (PDQ®)

Patient Version
Last Modified: 04/14/2014

Staging Primary CNS Lymphoma



After primary central nervous system (CNS) lymphoma has been diagnosed, tests are done to find out if cancer cells have spread within the brain and spinal cord or to other parts of the body.

When primary CNS lymphoma continues to grow, it usually does not spread beyond the central nervous system or the eye. The process used to find out if cancer has spread is called staging. It is important to know if cancer has spread to other parts of the body in order to plan treatment. The following tests and procedures may be used in the staging process:

  • 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).

  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do. A PET scan and CT scan may be done at the same time. This is called a PET-CT.

  • 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 body. This procedure is also called nuclear magnetic resonance imaging (NMRI).

  • Bone marrow aspiration and biopsy : The removal of bone marrow, blood, and a small piece of bone by inserting a hollow needle into the hipbone or breastbone. A pathologist views the bone marrow, blood, and bone under a microscope to look for signs of cancer.
    Enlarge
    Bone marrow aspiration and biopsy; drawing shows a patient lying face down on a table and a Jamshidi needle (a long, hollow needle) being inserted into the hip bone. Inset shows the Jamshidi needle being inserted through the skin into the bone marrow of the hip bone.
    Bone marrow aspiration and biopsy. After a small area of skin is numbed, a Jamshidi needle (a long, hollow needle) is inserted into the patient’s hip bone. Samples of blood, bone, and bone marrow are removed for examination under a microscope.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if primary CNS lymphoma spreads to the liver, the cancer cells in the liver are actually lymphoma cells. The disease is metastatic CNS lymphoma, not liver cancer.

There is no standard staging system for primary CNS lymphoma.