What is a lymphoma?

Lymphoma is a type cancer that starts in cells (called lymphocytes) that are part of the body's immune system. Just as cancer represents many different diseases, lymphoma represents many different cancers of lymphocytes - about 35 different subtypes, in fact.

It is important to know what type of lymphoma you have because it affects your treatment options.

Lymphomas fall into one of two major categories: Hodgkin's lymphoma (HL, previously called Hodgkin's disease) and all other lymphomas (non-Hodgkin's lymphomas or NHLs). There are five subtypes of Hodgkin's disease and about 30 subtypes of non-Hodgkin's lymphoma.

These two types occur in the same places, may be associated with the same symptoms, and often have similar appearance on physical examination. However, they are readily distinguishable via microscopic examination. Hodgkin's disease develops from a specific abnormal B lymphocyte lineage. NHL may derive from either abnormal B or T cells and are distinguished by unique genetic markers.

The exact causes of lymphoma are not known. Several factors have been linked to an increased risk of developing lymphoma, but it is unclear what role they play in the actual development of lymphoma.

These risk factors include the following: age, infections, medical conditions that compromise the immune system, exposure to toxic chemicals and genetics.

For more detailed info about lymphomas, visit emedicinehealth.com - Lymphoma (Hodgkin's Disease and Non-Hodgkin's Lymphoma).

Find out 30 Simple Ways You Can Prevent Cancer at Reader's Digest.