What is Hodgkin lymphoma?

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

• Hodgkin lymphoma
• Non Hodgkin lymphoma (NHL)

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

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

The cells of Hodgkin lymphoma have a particular appearance under the microscope. These cells are called Reed Sternberg cells. Non Hodgkin lymphomas do not have Reed Sternberg cells. Research has found 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 lymphoma and non Hodgkin 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 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.

The diagram below shows parts of the lymphatic system

Because the lymphatic system is all through the body, Hodgkin lymphoma can start just about anywhere. It can occur in more than one place in the body at the same time. The most common place for Hodgkin lymphoma to be noticed is in the lymph nodes in the neck. But it can start in any of the lymph nodes in the body, for example, in the chest, groin or abdomen, or under the arm.

You can also get Hodgkin lymphoma in body organs. Just over 1 in 10 people diagnosed have signs of Hodgkin lymphoma in the liver, bone or lung. About 1 in 3 people diagnosed have Hodgkin lymphoma in their spleen. The spleen is a large organ to the left of your stomach and it helps to process blood cells.

Hodgkin lymphoma can occur in either the tonsils or a gland in the chest called the thymus but this is very rare. Lymphoma in these sites is usually non Hodgkin lymphoma.

Some people have Hodgkin 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, breast cancer can spread to the lymph nodes close to the breast, so that the lymph nodes contain breast cancer cells. For information about cancer that has spread into the lymph nodes you need to look at the section about your cancer type.