Hodgkin's lymphoma is a cancer of the lymphatic tissue. This includes the lymph nodes, spleen, and bone marrow. The lymphatic system drains fluid from tissue and returns it to the blood. It plays an important role in the body's defense against infection.

What is going on in the body?

Hodgkin's lymphoma is a cancer that develops in a certain type of lymphatic cell. It causes lymphatic organs to become enlarged and spreads to the bone marrow and other tissues. The exact type of lymph cell that becomes cancerous remains controversial. But, when a Reed-Sternberg cell, or a large, unusual white cell, is seen in any tissue or blood specimen, it confirms the diagnosis of Hodgkin's lymphoma.

Sometimes Hodgkin's lymphoma is very slow growing. Other times it can spread quickly. It can restrict itself to one lymph node area. At other times, all lymph nodes, as well as the liver, spleen, and bone marrow, become involved. Hodgkin's lymphoma rarely spreads to the bones, brain, or kidneys.

What are the causes and risks of the disease?

The cause and risks of developing Hodgkin's lymphoma are not known. It might be caused by a virus, possibly the Epstein-Barr virus. A virus or combination of viruses could damage certain susceptible immune cells. This damage may change the genes that are responsible for lymph cell growth and regulation.

Hodgkin's lymphoma may be genetic. It seems to affect people with a higher education and socioeconomic level. People with immunodeficiency disorders, including AIDS, may be at risk. It is also linked to certain unusual infections. It may occur years after a person is cured of leukemia, another type of blood cancer. It is most common in people between the ages of 20 and 30, and again after the age of 50. Most children with Hodgkin's lymphoma are male.