Hodgkin's lymphoma

What is Hodgkin's lymphoma?

Hodgkin's lymphoma is a type of cancer in the lymphatic system. The lymphatic system is part of the immune system and functions to fight disease and infections.

The lymphatic system includes:

• Lymph - fluid containing lymphocyte cells.
• Lymph vessels - thin tubes that carry lymph fluid throughout the body.
• Lymphocytes - white blood cells that fight infection and disease.
• Lymph nodes - bean-shaped organs, found in the underarm, groin, neck, chest and abdomen, that act as filters for the lymph fluid as it circulates through the body.

Hodgkin's lymphoma causes the cells in the lymphatic system to abnormally reproduce, eventually making the body less able to fight infection and cause swelling in the lymph nodes. Hodgkin's lymphoma cells can also spread to other organs and tissue. A cancer cell that has spread to other organs and tissue is called "metastasis." It is a rare disease, accounting for less than 1 percent of all cases of cancer in the US. Hodgkin's lymphoma accounts for about 5 percent of childhood cancers. Hodgkin's lymphoma occurs most often in people between the ages of 15 and 34 and in people over age 55. The disease, for unknown reasons, affects males more than twice as often as females.

What causes Hodgkin's lymphoma in children?

The specific cause of Hodgkin's lymphoma is unknown. It is possible that a genetic predisposition and exposure to viral infections may increase the risk for developing Hodgkin's lymphoma. There is a slightly increased chance for Hodgkin's lymphoma to occur in siblings and cousins of patients.

There has been much investigation into the association of the Epstein-Barr virus (EBV) which causes the infection mononucleosis; as well as with human immunodeficiency virus (HIV), which causes acquired immune deficiency syndrome (AIDS). Both of these infectious viruses have been correlated with a greater incidence of children diagnosed with Hodgkin's lymphoma, although the direct link is unknown.

There are many individuals, however, who have infections related to EBV and HIV that do not develop Hodgkin's disease.

What are the symptoms of Hodgkin's lymphoma in children?

The following are the most common symptoms of Hodgkin's lymphoma. However, each child may experience symptoms differently. Symptoms may include:

• Painless swelling of the lymph nodes in neck, underarm, groin and chest.
• Difficulty breathing (dyspnea) due to a enlarged nodes in the chest.
• Fever.
• Night sweats.
• Tiring easily (fatigue).
• Weight loss/decreased appetite.
• Itching skin (pruritus).
• Frequent viral infections (i.e., cold, flu, sinus infection).

The symptoms of Hodgkin's lymphoma may resemble other blood disorders or medical problems. Always consult your child's physician for a diagnosis.

How is Hodgkin's lymphoma diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for Hodgkin's lymphoma may include:

• Blood and urine tests.
• X-rays of the chest - a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones and organs onto film.
• Lymph node biopsy - a sample of tissue is removed from the lymph node and examined under a microscope.
• Computed tomography scan of the abdomen, chest, and pelvis (Also called a CT or CAT scan) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat and organs. CT scans are more detailed than general x-rays.
• Lymphangiogram (LAG) - dye is injected into lymphatic system to determine the extent of lymphatic involvement in areas that are otherwise difficult to visualize.
• Bone marrow biopsy/aspiration - a procedure that involves a small amount of bone marrow fluid and tissue to be taken, usually from part of the hip bones, to further examine the number, size and maturity of blood cells or abnormal cells.

How is Hodgkin's lymphoma staged?

Staging is the process of determining whether cancer has spread and, if so, how far. There are various staging systems that are used for Hodgkin's lymphoma. Always consult your child's physician for information on staging. One method of staging Hodgkin's lymphoma is the following:

• Stage I - usually involves a single lymph node region or structure.
• Stage II - involves two or more lymph node regions or structures on the same side of the body.
• Stage III - involves lymph node regions or structures on both sides of the body and is further classified depending on the organs and areas involved.
• Stage IV - involves the disease in other areas (metastasis), in addition to the lymphatic system involvement

Stages are also noted by the presence or absence of symptoms of the disease:

• Asymptomatic (A).
• Symptomatic (B).

For example, stage IIIB is disease that is symptomatic, involves lymph node regions or structures on both sides of the body and is further classified depending on the organs and areas involved.

Treatment of Hodgkin's lymphoma in children

Specific treatment for Hodgkin's lymphoma will be determined by your child's physician based on:

• Your child's age, overall health and medical history.
• The extent/stage of the disease.
• Your child's tolerance for specific medications, procedures or therapies.
• Expectations for the course of the disease.
• Your opinion or preference.

Treatment may include (alone or in combination):

• Chemotherapy.
• Radiation.
• Surgery.
• Bone marrow transplant.
• Supportive care (for pain, fever, infection and nausea or vomiting).
• Continued follow-up care (to determine response to treatment, detect recurrent disease and manage side effects of treatment).

Aggressive therapy, while increasing long-term survival, also carries some serious side effects. Discuss with your child's physician a complete list of known side effects for treatment plans and therapies.

Long-term outlook for a child with Hodgkin's lymphoma

Prognosis greatly depends on:

• The extent of the disease.
• Presence or absence of metastasis.
• The response to therapy.
• Age and overall health of the child.
• Your child's tolerance of specific medications, procedures or therapies.
• New developments in treatment.

As with any cancer, prognosis and long-term survival can vary greatly from child to child. Every child is unique and treatment and prognosis is structured around the child. Prompt medical attention and aggressive therapy are important for the best prognosis. Continuous follow-up care is essential for the child diagnosed with Hodgkin's lymphoma. Side effects of radiation and chemotherapy, as well as second malignancies, can occur in survivors of Hodgkin's lymphoma. New methods are continually being discovered to improve treatment and to decrease side effects.