The lymphatic system

Lymphoma is a cancer of the lymphatic system. To help you understand it, it’s useful to know a bit about this system and what it does. The lymphatic system is part of the immune system. It helps to protect us from infection and disease and it drains fluid from the body’s tissues.

The lymphatic system is made up of:

  • white blood cells, called lymphocytes
  • lymphatic tissue, in the stomach, bowel, eye and thyroid gland
  • lymphatic organs, such as the bone marrow, tonsils, thymus, testicles, spleen and lymph nodes.
The lymphatic system
The lymphatic system

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Lymph nodes

There are groups of lymph nodes throughout the body including in the neck, armpits, groin, chest and tummy area (abdomen). They are connected by a network of fine tubes called lymphatic vessels. Lymph nodes filter disease and germs (bacteria and viruses) from lymph, a liquid that travels through the lymphatic vessels. Lymph nodes often swell when they are fighting infection. You may have noticed this if you’ve ever had a throat infection and felt swollen ‘glands’ in your neck just below your jaw.


Lymph nodes contain lots of infection-fighting white blood cells, called lymphocytes. There are also some lymphocytes in the lymph and blood.

There are two main types of lymphocyte: B-cell lymphocytes and T-cell lymphocytes.

Bone marrow

The bone marrow is a spongy material inside the bones. All the body’s blood cells, including lymphocytes, are made by special cells called stem cells inside the bone marrow.

There are three different types of blood cells, red cells, which carry oxygen to all cells in the body

white cells, which fight infection and platelets, which help blood to clot and control bleeding.

Back to Understanding non-Hodgkin lymphoma

What is cancer?

There are more than 200 different kinds of cancer, each with its own name and treatment.

What is non-Hodgkin lymphoma?

In non-Hodgkin lymphoma, blood cells called lymphocytes become abnormal. It is the fifth most common cancer in the UK.

Types of non-Hodgkin lymphoma

There are many types of non-Hodgkin lymphoma. These are often described as B-cell or T-cell lymphoma– depending on where they began.