Non-Hodgkin's Lymphoma

The lymphatic system is part of the body's immune system. It helps the body fight disease and infection. The lymphatic system includes a network of thin tubes that branch, like blood vessels, into tissues throughout the body. Lymphatic vessels carry lymph, a colorless, watery fluid that contains infection-fighting cells called lymphocytes. Along this network of vessels are small organs called lymph nodes. Clusters of lymph nodes are found in the underarm, groin, neck, chest, and abdomen. Other parts of the lymphatic system are the spleen, thymus, tonsils, and bone marrow. Lymphatic tissue is also found in other parts of the body, including the stomach, intestines, and skin.

In non-Hodgkin's lymphoma, cells in the lymphatic system become cancerous, that is, they divide and grow without any order or control, or old cells do not die as cells normally do. Because lymphatic tissue is present in many parts of the body, non-Hodgkin's lymphoma may occur in a single lymph node, a group of lymph nodes, or in another organ. This type of cancer can spread to almost any part of the body, including the liver, bone marrow and spleen.

Over the years, doctors have used a variety of terms to classify the many different types of non-Hodgkin's lymphoma. Most often, they are grouped by how quickly they are likely to grow and spread. Aggressive lymphomas, also known as intermediate and high-grade lymphomas, tend to grow and spread quickly and cause severe symptoms. Indolent lymphomas, also referred to as low-grade lymphomas, tend to grow slowly and cause fewer symptoms.

Possible Causes: The following are some of the factors associated with getting non-Hodgkin's lymphoma:

• Environment - People who work to a great degree with, or are otherwise exposed to certain chemicals, such as pesticides, solvents, or fertilizers, have a greater chance of developing non-Hodgkin's lymphoma.
• Viruses - T-lymphotropic virus type I (HTLV-1) and Epstein-Barr virus are two infectious agents that increase the chance of getting non-Hodgkin's lymphoma.
• Sex/Age - The likelihood of getting non-Hodgkin's lymphoma increases with age and is more common in men than in women.
• Weakened Immune System - Non-Hodgkin's lymphoma is more common among people with inherited immune deficiencies, autoimmune diseases, or HIV/AIDS, and among people taking immunosuppressant drugs following organ transplants.

People who are concerned about non-Hodgkin's lymphoma should talk with their doctor about the disease, the symptoms to watch for, and an appropriate schedule for checkups. The doctor's advice will be based on the person's age, medical history and other factors.

Symptoms: The most common symptom of non-Hodgkin's lymphoma is a painless swelling of the lymph nodes in the neck, underarm, or groin. Other symptoms may include the following:

• Unexplained weight loss
• Itchy skin
• Reddened patches on the skin
• Unexplained fever
• Night sweats
• Constant fatigue

When symptoms are present, it is important to see a doctor so that any illness can be diagnosed and treated as early as possible.

Stages: The doctor considers the following to determine the stage of non-Hodgkin's lymphoma:

• The number and location of affected lymph nodes
• Whether the disease has spread to the bone marrow, spleen, or to organs outside the lymphatic system such as the liver.
• Whether the affected lymph nodes are above, below, or on both sides of the diaphragm (the thin muscle under the lungs and heart that separates the chest from the abdomen).

In staging, the doctor may use some of the same imaging tests used for diagnosis of non-Hodgkin's lymphoma. A bone marrow biopsy involves removing a sample of bone marrow through a needle inserted into the hip or another large bone. A pathologist examines the sample under a microscope to check for cancer cells.