Lymphoedema of the arm is swelling of the arm due to a build up of lymphatic fluid in the tissues of that arm.

Usually when lymphoedema develops after treatment for a breast cancer it is due to either previous surgery or previous radiotherapy (or a combination of the two). Only very occasionally is it a sign of the cancer coming back.

Lymphoedema due to scarring, or damage, to the glands as a result of treatment can appear at any time. This may occur months or even years later.

It is unlikely that the lymphoedema you have noticed is a sign of cancer coming back. But you should see your doctor. He or she will check to make sure that there is no cancer.   You should also be referred to a lymphoedema specialist (often a nurse) who will assess you and give  treatment to control the lymphoedema and reduce the chances of it becoming a problem.