Non-hodgkin lymphomas

[Tracie Lynn]

Non-Hodgkin lymphomas are a diverse group of cancers that develop in B or T cells (lymphocytes).

Often, lymph nodes in the neck, under the arms, or in the groin enlarge rapidly and painlessly.
People may have pain or shortness of breath or other symptoms when enlarged lymph nodes press on organs.
A lymph node and/or bone marrow biopsy are needed for diagnosis.
Treatment may involve radiation therapy, chemotherapy, immunotherapy with monoclonal antibodies, or a combination.
Most people are cured or survive for many years.
People who relapse are treated with stem cell transplantation.

(See also Overview of Lymphoma and Hodgkin Lymphoma.)
Lymphomas are cancers of a specific type of white blood cells known as lymphocytes. These cells help fight infections. Lymphomas can develop from either B or T lymphocytes. T lymphocytes are important in regulating the immune system and in fighting viral infections. B lymphocytes produce antibodies, which are essential in fighting off some infections.
This group of cancers is actually more than 50 different diseases that involve B cells or T cells (lymphocytes), which are types of white blood cells. Each of these lymphomas has a distinct appearance under the microscope, a different cell pattern, and a different pattern of symptoms and progression. Most non-Hodgkin lymphomas (80 to 85%) are from B cells. Less than 15 to 20% develop from T cells.
Non-Hodgkin lymphoma is more common than Hodgkin lymphoma. It is the 6th most common cancer in the United States and causes 4% of all cancer deaths. It is more common as people get older.
In the United States, over 70,000 new cases are diagnosed every year, and the number of new cases is increasing, especially among older people and people whose immune system is not functioning normally. People who have had organ transplants and some people who have been infected with hepatitis C or the human immunodeficiency virus (HIV) are at risk of developing non-Hodgkin lymphoma.
Leukemias also are cancers that involve white blood cells. In leukemias, most of the cancerous white blood cells are in the bloodstream and bone marrow. In lymphomas, most of the cancerous white blood cells are within lymph nodes and organs such as the spleen and liver. However, leukemia and non-Hodgkin lymphoma sometimes overlap because people with lymphoma may have cancerous white blood cells in their bloodstream and people with leukemia may have cancer cells in their lymph nodes and organs.