Stages of AIDS-Related Lymphoma

After AIDS-related lymphoma has been diagnosed, tests are done to find out if cancer cells have spread within the lymph system or to other parts of the body.

The process used to find out if cancer cells have spread within the lymph system or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment, but AIDS-related lymphoma is usually advanced when it is diagnosed.

The following tests and procedures may be used to find out if the cancer has spread:

• MRI (magnetic resonance imaging) with gadolinium: A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as 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 (CSF) from the spinal column. This is done by placing a needle between two bones in the spine and into the CSF around the spinal cord and removing a sample of the fluid. The sample of CSF is checked under a microscope for signs that the cancer has spread to the brain and spinal cord. The sample may also be checked for Epstein-Barr virus. This procedure is also called an LP or spinal tap.

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.

The following stages are used for AIDS-related lymphoma:

Stage I

Stage I AIDS-related lymphoma is divided into stages I and IE.

• In stage I, cancer is found in one of the following places in the lymph system:
  • One or more lymph nodes in a group of lymph nodes.
  • Waldeyer's ring.
  • Thymus.
  • Spleen.
• In stage IE, cancer is found in one area outside the lymph system.

Stage II

Stage II AIDS-related lymphoma is divided into stages II and IIE.

• In stage II, cancer is found in two or more groups of lymph nodes that are either above the diaphragm or below the diaphragm.
• In stage IIE, cancer has spread from a group of lymph nodes to a nearby area that is outside the lymph system. Cancer may have spread to other lymph node groups on the same side of the diaphragm.

In stage II, the term bulky disease refers to a larger tumor mass. The size of the tumor mass that is referred to as bulky disease varies based on the type of lymphoma.

Stage III

In stage III AIDS-related lymphoma, cancer is found:

• in groups of lymph nodes both above and below the diaphragm; or
• in lymph nodes above the diaphragm and in the spleen.

Stage IV

In stage IV AIDS-related lymphoma, cancer:

• has spread throughout one or more organs outside the lymph system; or
• is found in two or more groups of lymph nodes that are either above the diaphragm or below the diaphragm and in one organ that is outside the lymph system and not near the affected lymph nodes; or
• is found in groups of lymph nodes both above and below the diaphragm and in any organ that is outside the lymph system; or
• is found in the liver, bone marrow, more than one place in the lung, or cerebrospinal fluid (CSF). The cancer has not spread directly into the liver, bone marrow, lung, or CSF from nearby lymph nodes.

Patients who are infected with the Epstein-Barr virus or whose AIDS-related lymphoma affects the bone marrow have an increased risk of the cancer spreading to the central nervous system (CNS).

For treatment, AIDS-related lymphomas are grouped based on where they started in the body, as follows:

Peripheral/systemic lymphoma

Lymphoma that starts in the lymph system or elsewhere in the body, other than the brain, is called peripheral/systemic lymphoma. It may spread throughout the body, including to the brain or bone marrow. It is often diagnosed in an advanced stage.

Primary CNS lymphoma

Primary CNS lymphoma starts in the central nervous system (brain and spinal cord). It is linked to the Epstein-Barr virus. Lymphoma that starts somewhere else in the body and spreads to the central nervous system is not primary CNS lymphoma.