Non Hodgkin’s Lymphoma (NHL) refers to a group of cancers that affect the body’s lymphoid system. Approximately 55,000 cases of non Hodgkins lymphoma are diagnosed in the U.S. each year. The incidence of non-Hodgkin lymphoma has been increasing in the U.S. during the past two decades at the rate of approximately 3% per year.
Lymphoma was first described by the British physician Thomas Hodgkin. The specific type of cancer he reported is now known as Hodgkin’s disease. All other types of lymphomas are considered non-Hodgkin’s lymphomas.
The lymphoid system, which is a network of cells and channels that run throughout the body, is a very important part of the immune system. Lymphoid system cells, known as “lymphocytes,” form in clusters known as “lymph nodes” and “lymph glands.” Lymphocytes travel throughout the body to all the tissues of the body. Because these cells circulate throughout the body, lymphoma cancers can form in virtually any organ. At the time of diagnosis, a lymphoma cancer might be present in just a lymph node or organ, or in many different parts of the body.
The World Health Organization (WHO) has identified nearly 30 subtypes of non-Hodgkin’s lymphoma. These subtypes are typically categorized as “indolent” lymphomas, “moderately aggressive” lymphomas, and “highly aggressive” lymphomas. “Indolent” lymphomas affect lymph nodes, bone marrow, and/or the spleen. “Aggressive” lymphomas are mainly found in the lymph nodes, but some cases affect organs that are separate from the lymph nodes (called “extranodal” cases).
The symptoms of non Hodgkin’s lymphoma can vary from patient to patient, depending on such factors as the location of the cancer. One of the most common symptoms is an enlarged lymph node. Other symptoms can include fever, chills, night sweats, loss of appetite, fatigue, and unexplained weight loss. Symptoms can also be specifically related to the part of the body or organ that the lymphoma is affecting.