Lymphoma is the third most common childhood cancer. It is cancer of the lymphatic system, which is made up of thin tubes that branch like blood vessels into all parts of the body. These lymph vessels carry lymph, a colorless, watery fluid containing white blood cells called lymphocytes. Along the network of vessels are lymph nodes, groups of small, bean-shaped organs that make and store infection-fighting cells.
There are clusters of lymph nodes in the underarm, groin, neck and abdomen. The lymph system also includes the spleen, the thymus and the tonsils. Because the lymph system is so extensive, lymphoma can start in many locations and spread to almost any organ or tissue.
There are two types of lymphoma — Hodgkin's and non-Hodgkin's. The cause for both diseases is unknown and it occurs in one child in 10,000. Hodgkin's disease typically affects those age 14 and older.
Hodgkin's lymphoma often occurs in one or more groups of lymph glands, most commonly in the neck. The first symptom is usually swollen glands. Often, the cancer is limited to a small number of closely related glands. In half of the children affected, it spreads to the chest.
The disease occurs in three distinct forms:
Hodgkin's disease peaks in young adults and again in those over 50 years of age. It is slightly more common in males than females, and is more common in Caucasians. This disease is very rare in children younger than 5 and tends to cluster in families. The main malignant cell of Hodgkin's lymphoma is the "Reed-Sternberg" cell that originates from B or T cells, cells that contain antibody molecules. Several types of Hodgkin's disease also are associated with the Epstein-Barr virus, a member of the herpes virus family and one of the most common human viruses.
Four types of Hodgkin's disease are:
The first symptom of Hodgkin's lymphoma is usually swollen lymph glands. In a minority of children, there is high fever, weight loss and night sweats. These symptoms are more common if the cancer is extensive.
Many of the symptoms of Hodgkin's lymphoma are general in nature and could be caused by other conditions such as infections.
Your child's doctor may request a number of diagnostic tests, including:
The most common treatments for Hodgkin's disease are radiation or chemotherapy and sometimes a combination of the two. Treatments may vary depending on the stage of the cancer and whether your child has reached full growth. Chemotherapy uses drugs to kill cancer cells and shrink tumors. Radiation therapy involves high-dose X-rays or other high-energy rays to kill cancer cells and shrink tumors. Bone marrow transplantation is being tested in patient studies for those with advanced disease.
The prospect for curing children with stage I or II disease is about 90 percent, and more than 50 percent for those with widespread disease, even children with stage IV.
Reviewed by health care specialists at UCSF Benioff Children's Hospital.