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Supporting people with non-Hodgkin's lymphoma
What is non-Hodgkin's lymphoma?


  • Lymphoma is like a cancer of lymphocytes
  • Abnormal lymphocytes multiply and collect in lymph nodes - causing them to swell - and can also collect in other places, like the spleen and bone marrow
  • The swellings cause many of the symptoms of lymphoma
  • Other symptoms result from the abnormal lymphocytes not being able to prevent infection
  • There are two main types of lymphoma - Hodgkin's lymphoma and non-Hodgkin's lymphoma
  • Non-Hodgkin's lymphoma is further split into indolent and aggressive forms of the disease


Lymphoma is a disease of the lymphocytes. It is like a cancer, in that the affected lymphocytes stop being regulated in the normal way. In other words, they may divide abnormally or too quickly, and/or they may not die off in the way they ought to. The abnormal lymphocytes often collect in the lymph nodes, which become swollen as a result.

Because lymphocytes circulate throughout the body, lymphomas - collections of abnormal lymphocytes - can also form in parts of the body other than the lymph nodes.The spleen and the bone marrow are common sites for lymphomas to form outside the lymph nodes, but some people develop a lymphoma of the stomach, the liver or rarely of the brain. Indeed, a lymphoma can form almost anywhere. It is also common for more than one part of the body to be affected by the disease.

In general, because of the circulatory nature of the lymph, lymphomas are usually referred to as diseases that affect the whole body, and not just the area that is obviously affected by swollen glands. These conditions are known as 'systemic diseases'.

Many of the symptoms of lymphoma arise because of the swellings caused by the collections of abnormal lymphocytes. The precise symptoms depend on where in the body the swellings are. In addition, the abnormal lymphocytes are not able to fulfil their normal role in the body's immune system and, without treatment, a person with lymphoma is likely to become more prone to infection.

Lymphomas can be divided into two main groups:

  • Non-Hodgkin's lymphoma (sometimes written as non-Hodgkins lymphoma, without the apostrophe, or non-Hodgkin lymphoma, and often known simply as NHL)
  • Hodgkin's lymphoma (also known as Hodgkin's disease)

This website is concerned only with non-Hodgkin's lymphoma.

Non-Hodgkin's lymphoma is a disease that affects the cells of the lymphatic system known as lymphocytes. Click on the picture to see an animated diagram explaining non-Hodgkin's lymphoma
Animated diagram explaining non-Hodgkins lymphoma

Non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma is one of the two main groups of lymphoma (the other being Hodgkin's lymphoma). The cells in a non-Hodgkin's lymphoma look and behave differently from those in a Hodgkin's lymphoma.

It is important to know exactly what form of non-Hodgkin's lymphoma a patient has, how fast it is developing, where it is in the body, and how far it has spread. To work this out, the disease is subdivided by:

  • Classification or grading - this tells doctors whether the non-Hodgkin's lymphoma is indolent (low-grade, or slow growing) or aggressive (high-grade, or fast growing)
  • Type - within the classifications of indolent or aggressive, the disease is further divided into over 30 types, depending on how samples of cells, usually taken by biopsy, look under the microscope. This is also referred to as the 'grade'

  • Stage - to indicate where the lymphoma is in the body and how much it has spread, the disease is divided into stages I, II, III and IV. Along with the patient's medical history and the physical examination, staging involves tests such as X-rays, CT scans, PET scans, bone marrow biopsies and blood tests

This information - the classification, the type and the stage - helps doctors to predict the way in which a particular non-Hodgkin's lymphoma will behave and how the patient is likely to be affected. It is also very important to plan the correct treatment, so all the information must be available before treatment is planned and started.


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