Inherited lymphoedema is known as primary lymphoedema. This is generally caused by a malformation of the lymphatic vessels or lymph nodes, or the complete absence of lymphatic vessels. Primary lymphoedema usually becomes apparent before the age of 35.

Oedema that is acquired in the course of a person’s life is called secondary lymphoedema. This can arise due to a variety of factors:

• Inflammation, which allows more tissue fluid to be formed than the lymphatic vessels can transport away,
• Injuries to the lymphatic vessels, often caused by operations. Lymphoedema in the arms frequently occurs in women who have undergone surgery for breast cancer, in whom lymph nodes in the armpits are removed.
• Malignant tumours with an accumulation of cancer cells in the lymph nodes.
• Damage caused by irradiation, by which the walls of the lymphatic vessels adhere together.