Non-Hodgkin’s lymphoma (NHL) is a malignancy of the lymph system. NHL is related to another lymphoma, Hodgkin’s disease, but accounts for the majority of lymphoma diagnoses.
Generally speaking, a lymphoma is a tumor of the lymphatic system, which is located throughout the body. The lymphatic system produces and transports lymphocytes, or white blood cells, which make up the immune system. Lymphocytes produce antibodies that, in turn, attack foreign agents that may enter the body. The lymph system is considered the body’s best defense against infectious organisms.
The incidence of NHL in the United States since the 1970s has practically doubled. NHL is now the sixth most common malignancy in the States, accounting for 7 percent of new malignancy cases. Approximately 57,000 new cases of NHL are diagnosed every year. NHL is found more commonly in men than in women. People of any age can develop it, but onset age for NHL is generally between ages 45 and 60.
Certain people may be at risk for developing NHL, although experts have not drawn any real conclusions on this front. Some risk factors that are being investigated are: infection with the AIDS virus, antibiotic use, exposure to ultraviolet rays from sunlight, exposure to chemicals and pesticides, and immune-suppressive medications.
Though the cause of the disease is unknown, some studies have found a link between an increased risk for lymphoma and high consumption of red meat. Farmers, painters, and lumberjacks who are in contact with industrial and agricultural chemicals were shown in some studies to be at a higher risk for NHL.
More than 20 types of NHLs exist. The types are classified according to a standard called REAL, the Revised European-American Lymphoma Classification. The system ranks the lymphoma according to appearance, type, and genetic make-up, as well as by how aggressive the disease is. NHL is usually found in the lymph nodes of the chest, abdomen, neck, tonsils, and skin. It may also develop outside the lymph nodes in the digestive tract.