Lymphoma is cancer that starts in the lymph glands or other organs of the lymphatic system. The lymphatic system is a network of fine vessels, glands and channels which occur throughout the body.

It also conveys nutrients and cells, and is responsible for draining fluid and waste products away from tissues, and into the blood stream to be processed. The lymphatic system is an important part of the immune system and is made up of lymph nodes and vessels and of collections of lymphocytes in other tissues.

Lymphoma happens when some of the lymphocytes divide in an abnormal way, or do not die as they should. They can collect in the lymph nodes which enlarge as tumours form. Lymphoma is not necessarily restricted to one part of the body, it can also involve other organs and affect the function of the tissue involved.

There are two main types of lymphoma:

  • Hodgkin lymphoma (formerly known as Hodgkin’s disease)
  • Non-Hodgkin lymphoma (formerly known as Non-Hodgkin’s lymphoma)

It’s only possible to tell the difference between Hodgkin lymphoma and non-Hodgkin lymphoma when the cells are looked at under a microscope.

In almost all cases of Hodgkin lymphoma, a particular cell called the Reed-Sternberg cell is found when cells from the lymph node are examined during diagnosis. This cell isn’t usually found in other types of lymphoma, so these types are called non-Hodgkin lymphoma.

This difference is important, because the treatment for Hodgkin and non-Hodgkin lymphoma can be very different. It’s thought that Reed-Sternberg cells are a type of white blood cell – a B-cell that has become cancerous. B-cells normally make antibodies to fight infection.

Lymphoma is the most common blood cancer in young people aged 15 to 24.

The most common sign of the condition is often a painless swelling in the neck, armpit or groin that is caused by enlarged lymph nodes.

Other common symptoms include:

  • Excessive sweating, especially at night
  • Fevers
  • Unexplained loss of weight
  • Unusual tiredness
  • Persistent itching
  • Abdominal pain or diarrhoea
  • Bruising
  • Recurrent infections

Please remember each disease may differ in both character and treatment.

For expert support and advice about Lymphoma, please visit the Lymphoma Action website.