The body’s lymphatic system filters the blood and helps to fight infection. It is made up of a network of lymph vessels that transport lymph fluid throughout the body. Along the lymph vessels are many small, bean-shaped structures known as lymph nodes (glands).

Sometimes radiation therapy damages lymph nodes or lymph vessels in the area being treated, especially if some lymph nodes have already been removed by surgery. Because the lymph fluid no longer drains properly, it can build up and cause part of the body to swell. This swelling is known as lymphoedema. It usually occurs in an arm or leg, but can also affect other parts of the body.

Lymphoedema or swelling is sometimes just a temporary effect of radiation therapy, but it can be ongoing. It can also be a late effect, appearing months or even years after the treatment.

Early diagnosis of lymphoedema allows the condition to be well managed, so let your treatment team know if any new swelling appears. In some hospitals, a lymphoedema practitioner can assess your risk of developing lymphoedema and give you some simple exercises to help you reduce your risk and regain movement. To prevent lymphoedema getting worse, it is very important to avoid infection in the swollen area.

For more information about lymphoedema, call Cancer Council 13 11 20 or go to Lymphoedema.

Radiation therapy can cause the skin or internal tissue to become less stretchy and harden. This is known as fibrosis. It can occur weeks or months after treatment and have a range of impacts, such as pain, lack of flexibility and narrowing of passages (such as the vagina or rectum). Let your treatment team know if you start experiencing any new pain or stiffness, as early treatment can help.

This information was last reviewed in December 2017
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Lymphoedema is swelling (oedema) that occurs when lymph fluid builds up in the tissues under the skin.

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