Non-Hodgkin’s lymphoma (NHL) refers to a group of closely related types of lymphomas that have some common characteristics.1,2 Lymphoma is a type of cancer that arises from within the lymphatic system (the body’s immune system) and is made up of tissues and organs that help in fighting off infections and certain diseases.3,4 These various tissues and organs include the tonsils, thymus, spleen, bone marrow, lymph vessels, and lymph nodes.2 Lymph tissue is also found in many other parts of the body, including the small intestine.2 Descriptions of each element of the lymphatic system are listed below:
A type of white blood cell which fights infection and disease. There are three types of lymphocytes – B cells, T-cells and natural killer (NK) cells. Most NHL types originate from B-cells.2
Small, bean-shaped structures which contain the body’s immune cells, including lymphocytes. They can be found inside the chest, abdomen, and pelvis. Various sites are connected via a network of lymphatic vessels (green vessels in the figure) making up the lymphatic system.1,2
An organ located in the abdomen that produces various immune system cells such as lymphocytes. It also stores healthy blood cells and helps to filter our damaged blood cells as well as foreign and bodily waste. The spleen lies under the lower ribs on the left side of the body.1,2
A spongy tissue contained inside certain bones where new blood cells are produced.1,2
An organ located behind the upper part of the breastbone and in front of the heart; it is essential in the development of one type of lymphocytes called T-lymphocytes.1,2
These are masses of lymph tissue located at the back of the throat, which help fight germs that are breathed in or swallowed.1,2
Various parts of the digestive tract have lymph tissue including the stomach and intestine.1,2
NHL can be categorized in different types based on factors such as type of lymphocyte it developed from as well as how it grows and spreads.2 These factors can affect experienced symptoms, time to diagnosis, possible treatment options and overall survival.2 Affected lymph nodes located next to each other and NHL that is new or that has returned after treatment (recurrent) can impact treatment as well.2
Lymphoma based on cell type
While NHL can occur in any of the lymphocyte cell types, B-cell lymphomas comprise about 85% of NHLs. B-cells fight infections by producing antibodies.3 The focus of this site is B-cell lymphomas.
Lymphoma based on growth and spread
NHLs are also classified as indolent, meaning it grows and spreads slowly, or aggressive, meaning it grows and spreads quickly. Indolent lymphomas may have few signs or symptoms, whereas symptoms may be severe with aggressive types.2 And while both types are equally common among adults, children are more prone to the aggressive NHL.2 Some types of NHL have both indolent and aggressive characteristics, for eg, mantle cell lymphoma.5
Indolent lymphomas, while typically not curable, are treatable and patients with these types of NHL can live long lives while in remission. If NHL is recurrent, lymphomas initially determined as indolent may return as aggressive, and vice versa.2 Aggressive lymphomas are often curable.6
The reasons that make certain individuals susceptible to developing NHL are not currently understood. There are certain risk factors that may increase your chances of getting NHL or even certain NHL types.2 However, having one or more risk factors is not a certainty to developing NHL.5 Risk factors, based on whether they are modifiable or not, are tabulated here.
All URLs accessed July 2, 2024
