What are lymph nodes?
Lymph nodes or lymph glands, are part of the lymphatic system which is part of both the immune and circulatory systems. The lymphatic system consists of lymph vessels, lymph fluid and lymph nodes and other lymph tissue.
Lymph nodes are small, bean-shaped structures that are found along the lymph vessels. They filter lymph fluid as it passes through your body before emptying into the bloodstream. Lymph fluid, which is normally clear, travels to and from the tissues in your body. It carries nutrients but also takes away harmful substances such as bacteria, viruses, cell debris and abnormal cells such as cancer cells. The filtered fluid is returned to your blood circulation.
Where are lymph nodes located?
There are hundreds of lymph nodes found throughout your body, including your armpits, groin, neck, between your lungs and around your gut. The lymph nodes drain lymph fluid from nearby organs or other areas of your body.
Other lymph tissue is found in other parts of your body including the thymus, tonsils, spleen and bone marrow.
How are lymph nodes affected by cancer?
Cancer can appear in the lymph nodes in two ways. It can start in the lymph nodes (lymphoma) or it can spread from where the cancer started (the primary site) elsewhere in the body such as the breast or bowel. Most commonly the cancer begins somewhere else and spreads to the lymph nodes. If you are diagnosed with cancer, your doctor will examine your lymph nodes to see if they are affected by the cancer.
Cancer or cancer treatment can block or damage the lymphatic system which may stop it from working properly. As a result, lymph fluid doesn’t drain properly and builds up in the tissues causing swelling (lymphoedema) although there are ways to reduce the risk.
For more information talk to your doctor or call Cancer Council 13 11 20.
Understanding lymphoedema fact sheet, Cancer Council Australia © 2019. Last medical review of source booklet: July 2021.
Last reviewed January 2019
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