What is Hodgkin's lymphoma?

• A quick guide to what's on this page
• Types of lymphoma
• The lymphatic system
• Where in the body you get Hodgkin's lymphoma

Lymphoma means a cancer of the lymphatic system. There are two main types of lymphoma

• Hodgkin's lymphoma
• Non-Hodgkin's lymphoma (NHL)

Most lymphomas are NHL. Only about 1 in 5 are Hodgkin's lymphoma. Hodgkin's disease was named after the doctor who first recognised it in 1832 - Thomas Hodgkin. It is now called Hodgkin's lymphoma.

Remember - if you are looking for information about non Hodgkin's lymphoma, this is not the right section of CancerHelp UK for you. This link takes you to information about non Hodgkin's lymphoma. This section is only about Hodgkin's lymphoma in adults.

The cells of Hodgkin's lymphoma have a particular appearance under the microscope. These cells are called Reed Sternberg cells. Non Hodgkin's lymphomas do not have Reed Sternberg cells. Research has convinced most scientists that Reed Sternberg cells are a type of white blood cell called a B lymphocyte, which has become cancerous. B lymphocytes normally make antibodies to help fight infections.

It is important for doctors to be able to tell the difference between Hodgkin's lymphoma and non-Hodgkin's lymphoma cells. They are two different diseases. And although they are very similar in many ways, the treatment for them is quite different.

 In Hodgkin's lymphoma, it is cells in the lymph nodes that have become cancerous. Lymph nodes are bean shaped glands found all over the body that are part of the lymphatic system. They are connected by very fine tubes called lymph vessels (or lymphatics). Tissue fluid circulates around the body in these vessels and flows through the lymph glands. The lymph glands filter germs out of the fluid and contain specialised white blood cells, which kill any bacteria or viruses they find. This explains why your lymph glands swell when you have an infection. There is more about lymph nodes and about what the lymphatic system does in the about your body section of CancerHelp UK.

The diagram below shows parts of the lymphatic system

Because the lymphatic system runs all through the body, you can get Hodgkin's lymphoma just about anywhere. The most common place for Hodgkin's lymphoma to be noticed is in the lymph nodes in the neck. But you may notice it first in lymph nodes anywhere in the body, for example, in the chest, groin or abdomen or under the arm.

You can also get Hodgkin's lymphoma in body organs. About 1 in 20 people diagnosed have signs of Hodgkin's lymphoma in the liver, bone or lung. About 1 in 3 people diagnosed have Hodgkin's lymphoma in their spleen. (The spleen is a large organ to the left of your stomach. It helps to process blood cells.)

It is not usual to get it in either the tonsils or a gland in the neck called the thymus. Lymphoma in these sites is usually non-Hodgkin's lymphoma.

Some people have Hodgkin's lymphoma in parts of the body outside the lymphatic system and this is called extranodal disease.

Remember - it is very common for other types of cancer to spread to lymph nodes. This is not lymphoma. For example, positive lymph nodes in breast cancer contain breast cancer cells, not lymphoma cells. For information about breast cancer that has spread to the lymph nodes, you should look in the breast cancer section. For information about lung cancer that has spread to the lymph nodes, look at the lung cancer section, and so on.