Non-Hodgkins Lymphomas (cont.)

Medical Author:

Jerry R. Balentine, DO, FACEP

Jerry R. Balentine, DO, FACEP

Dr. Balentine received his undergraduate degree from McDaniel College in Westminster, Maryland. He attended medical school at the Philadelphia College of Osteopathic Medicine graduating in1983. He completed his internship at St. Joseph's Hospital in Philadelphia and his Emergency Medicine residency at Lincoln Medical and Mental Health Center in the Bronx, where he served as chief resident.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Non-Hodgkin's lymphoma is a type of cancer that originates in the lymphatic system. It is estimated to be the sixth most common cancer in the United States. The lymphatic system is part of the body's immune system and helps fight infections and other diseases. In addition, the lymphatic system filters out bacteria, viruses, and other unwanted substances.

The lymphatic system consists of the following:

Lymph vessels: These vessels branch out throughout the body similar to blood vessels.

• Lymph: The lymph vessels carry a clear fluid called lymph. Lymph contains white blood cells, especially lymphocytes such as B cells and T cells.
• Lymph nodes: Lymph vessels are interconnected to small masses of lymph tissue called lymph nodes. Lymph nodes are found throughout the body. Collections of lymph nodes are found in the neck, underarms, chest, abdomen, and groin. Lymph nodes store white blood cells. When you are ill and the lymph nodes are active, they will swell and be easily palpable (your doctor can feel them when she examines you).
• Additional parts of the lymphatic system: The tonsils, thymus, and spleen are additional components of the lymphatic system. Lymphatic tissue is also found in other parts of the body, including the stomach, skin, and small intestine.

Because lymphatic tissue is found in many parts of the body, non-Hodgkin's lymphoma can start almost anywhere.

We don't know what causes non-Hodgkin's lymphoma (NHL). NHL occurs when your body produces too many abnormal lymphocytes. In the normal life cycle of lymphocytes (a type of white blood cell), old lymphocytes die and your body creates new ones to replenish the supply. In NHL, lymphocytes grow indefinitely, so the number of circulating lymphocytes increases, filling up the lymph nodes and causing them to swell.

In NHL, either B cells or T cells are involved in this process. These are the two subtypes of lymphocytes.

B cells produce antibodies that fight infections. This is the most common type of cell involved in NHL.

T cells kill the foreign substances directly. NHL less frequently originates from T cells.

The following are some of the common subtypes of NHL:

Burkitt's lymphoma: This lymphoma has two major subtypes, an African type closely associated with an infection with the Epstein-Barr virus and the non-African, or sporadic, form that is not linked to the virus.

Diffuse large cell lymphoma: This represents the most common lymphoma (approximately 30% of NHL) and can be rapidly fatal if not treated.

Follicular lymphoma: These lymphomas exhibit a specific growth pattern when viewed under the microscope (follicular or nodular pattern); they are usually advanced at the time of diagnosis.

MALT lymphoma: This is a B cell lymphoma that usually affects individuals in their 60s. The most common area for this lymphoma to develop is the stomach.

Mantle cell lymphoma: One of the rarest of the NHL, mantle cell lymphoma accounts for about 6% of cases. This NHL is difficult to treat and is a subtype of B cell lymphoma.

Adult T cell lymphoma/leukemia: This is a rare but aggressive NHL of the immune system's T cells. Human T cell leukemia/lymphotropic virus type (HTLV-1) is believed to be the cause.

Source: MedicineNet.com
http://www.medicinenet.com/non-hodgkins_lymphomas/article.htm