Overview of AIDS-Related Lymphoma
AIDS-related lymphoma is a disease in which cancerous (malignant) cells are found in the lymph system in patients who have AIDS (acquired immunodeficiency syndrome). AIDS is caused by the human immunodeficiency virus (HIV), which attacks and weakens the immune system. Infections and other diseases can then invade the body, and the immune system cannot fight against them.
The lymph system, or lymphatic system, is made up of thin tubes that branch, like blood vessels, into all parts of the body. Lymph vessels carry lymph, a colorless, watery fluid that contains white blood cells called lymphocytes. Along the network of vessels are groups of small, bean-shaped organs called lymph nodes. Clusters of lymph nodes make and store infection-fighting cells.
The spleen (an organ in the upper abdomen that makes lymphocytes and filters old blood cells from the blood), the thymus (a small organ beneath the breastbone), and the tonsils (an organ in the throat) are also part of the lymph system. Because there is lymph tissue in many parts of the body, the cancer can spread to almost any of the body's organs or tissues including the liver, bone marrow (the spongy tissue inside the large bones of the body that makes blood cells), spleen, or brain.
Types of Lymphoma
Lymphomas are divided into two general types, Hodgkin's disease and non-Hodgkin's lymphomas, which are classified by the way their cells look under a microscope. This determination is called the histology.
Histology is also used to determine the type of non-Hodgkin's lymphomaof which there are ten. The types of non-Hodgkin's lymphomas are classified by how quickly they spread: low-grade, intermediate-grade, or high-grade. The intermediate- or high-grade lymphomas grow and spread faster than the low-grade lymphomas.
Both major types of lymphoma, Hodgkin's disease and non-Hodgkin's lymphoma, may occur in AIDS patients. Also, the intermediate- and high-grade types of non-Hodgkin's lymphoma are more commonly found in AIDS patients. Both types of lymphomas can occur in adults and in children.
Signs and Symptoms of Lymphoma
A doctor should be seen if any of the following symptoms persist for longer than 2 weeks:
- Painless swelling in the lymph nodes in the neck, underarm, or groin
- Night sweats
- Unexplained weight loss
- Itchy skin
If a patient has AIDS and symptoms of lymphoma, a doctor will carefully check for swelling or lumps in the neck, underarms and groin. If the lymph nodes are abnormal, the doctor may need to remove a small piece of tissue and examine it under the microscope to see if there are any cancer cells. This procedure is called a biopsy.
In general, lymphomas are classified by: (1) how rapidly they grow, (2) how cureable they are, and (3) similarities in overall survival and disease free survival.
In general, patients with AIDS-related lymphoma respond to treatment differently from patients with lymphoma who do not have AIDS. AIDS-related lymphoma usually grows faster and spreads outside the lymph nodes and to other parts of the body more often than lymphoma that is not related to AIDS. Because therapy can damage weak immune systems even further, patients who have AIDS-related lymphoma are generally treated with lower doses of drugs than patients who do not have AIDS.
Stages of AIDS-Related Lymphoma
Once AIDS-related lymphoma is diagnosed, more tests will be done to find out if the cancer has spread from where it started to other parts of the body. This testing is called staging. The stage of a disease, ranging from Stage I to Stage IV, gives an indication of how far the disease has spread. To plan treatment, a doctor needs to know the stage of the disease.
The doctor may determine the stage of the disease by conducting a thorough examination which may include blood tests and different kinds of X-rays. This testing is called clinical staging.
In some cases, the doctor may need to do an operation called a laparotomy to determine the stage of the cancer. During this operation, the doctor cuts into the abdomen and carefully looks at the organs to see if they contain cancer. The doctor will remove small pieces of tissue and look at them under a microscope (biopsy) to see whether they contain cancer. This type of staging is called pathologic staging. Pathologic staging is usually done only when it is needed to help the doctor plan treatment.
For treatment, AIDS-related lymphomas are grouped based on where they started, as follows:
- Systemic/Peripheral LymphomaLymphoma that has started in lymph nodes or other organs of the lymph system. The lymphoma may have spread from where it started throughout the body, including to the brain or bone marrow.
- Primary Central Nervous System LymphomaLymphoma that has started in the brain or spinal cord, both of which are part of the central nervous system (CNS). This type of lymphoma is called a "primary CNS lymphoma" because it starts in the CNS rather than starting somewhere else in the body and spreading to the CNS.
To Learn More about AIDS-Related Lymphoma
To learn more about AIDS-related lymphoma, visit the National Cancer Institute Cancer Information Service or call them at 1.800.4.CANCER (1.800.422.6237); TTY at 1.800.332.8615. By dialing this toll-free number, trained information specialists can help answer your questions.
National Cancer Institute
Office of Cancer Communications
31 Center Drive, MSC 2580
Bethesda, MD 20892-2580