About lymphomas and the lymphatic system

NHL is a cancer of the lymphatic system. Learning more about the lymphatic system can help you understand it better.

The lymphatic system is one of the body’s natural defences against infection. Lymph nodes (sometimes called lymph glands) are an important part of the lymphatic system. They are connected by a network of tiny tubes called lymph vessels. There are groups of lymph nodes throughout the body including in the tummy area (abdomen), chest (mediastinum), neck, armpit and groin (where the top of your leg joins your body).

A fluid called lymph travels through the lymphatic vessels. Lymph carries white blood cells called lymphocytes around the body to fight infections and disease.

Lymphocytes start in the bone marrow as cells that haven’t properly developed yet (immature), called stem cells. They then go through different stages of development until they are fully developed (mature), and ready to fight infections and disease. The two main types of lymphocytes are called T-cells and B-cells.

Lymphomas

Lymphomas, like all cancers, are a disease of the body’s cells. Normally cells in our body divide and grow in a controlled way. But sometimes cells keep dividing and grow out of control. This is how cancer develops.

In lymphomas, white blood cells called lymphocytes become abnormal and grow out of control. These lymphocytes can build up in one part of the body and form a lump (tumour).

There are two main types of lymphoma:

• Hodgkin lymphoma
• non-Hodgkin lymphoma (NHL).

Although these cancers are both lymphomas, they are different and need different treatments. Your doctors will do tests to find out which type you have.

The most common place for NHL to start is in the lymph nodes. But NHL can begin in almost any part of the body, including in the stomach, skin or tonsils.

Lymphoma that grows outside the lymph nodes is called extranodal lymphoma.

Because lymphocytes travel around the body, NHL can spread from where it first started.

It can spread through:

• the lymphatic system, from lymph nodes in one part of the body to lymph nodes elsewhere
• the bloodstream to other parts of the body such as the spleen or bone marrow.

When the lymphoma cells reach a new area they may start growing and form a new lump (tumour).

Causes 

We don't know what causes NHL, but research is going on to try to find out. Remember that nothing you’ve done has caused the cancer.

NHL isn’t infectious and can’t be passed on to other people or family members. It also doesn’t run in families, so if one person in the family has had it, that doesn’t mean that the rest of the family is more likely to get it.