The following is provided by the National Cancer Institute

Hodgkin's disease (also known as Hodgkin's lymphoma) is a type of cancer that develops from cells in the lymph system (part of the body's immune system) called lymphocytes (a subset of white blood cells responsible for immunity and fighting infections).

There are two basic categories of lymphomas: Hodgkin's lymphoma and non-Hodgkin's lymphomas. The difference between these is in the specific lymphocytes involved. Hodgkin's lymphoma is marked by the presence of an abnormal lymphocyte called the Reed-Sternberg cell (or B lymphocyte).

Hodgkin's disease is very rare and comprises less than one percent of all cancers diagnosed in the United States. According to the Lymphoma Research Foundation of America, Hodgkin's lymphoma is more curable than non-Hodgkin's lymphoma. The cure rate varies according to the type of disease.

Most people who develop Hodgkin's disease are between the ages of 15-34, or over age 55. Evidence suggests that Hodgkin's disease is more common in those with a family history of the illness.

According to the National Cancer Institute, researchers have found certain risk factors that are more common in people who get Hodgkin's disease than in those who do not. However, most people with these risk factors do not get Hodgkin's disease, and many who do get this disease have none of the known risk factors.
The following are some of the risk factors associated with this disease:

Age/sex: Hodgkin's disease occurs most often in people ages 15-34 and in people over the age of 55. It is more common in men than in women.

Family history: Brothers and sisters of those with Hodgkin's disease have a higher-than-average chance of developing this disease.

Viruses: According to the Lymphoma Research Foundation of America, it is now known that environmental toxins such as pesticides can increase the risk of developing lymphoma. People with HIV, the Epstein-Barr Virus or who are taking immunosuppressive drugs (such as kidney or lung transplant patients) are at greater risk for developing Hodgkin's disease.

Treatment for Hodgkin's disease depends on the stage of the disease, the size, the number and location of the affected lymph nodes, the symptoms you're experiencing, and your age and general health.