Lymphedema is the build-up of lymph fluid in the body’s tissues due to damage in the lymphatic system. It occurs when the lymph system cannot remove the fluid it normally does from the tissue. This build-up causes abnormal swelling, often of an arm or leg. Lymphedema can be primary or secondary.
Primary lymphedema is seen in people who are born with abnormalities in the lymphatic system.
Secondary lymphedema is a complication that can occur after cancer treatments (e.g. surgery, lymph node removal, radiation therapy). Lymphedema is usually seen in the part of the body that had the
specific cancer treatment. Secondary lymphedema is the most common type of lymphedema in
North America. It is important not to confuse lymphedema with water retention. Lymphedema is a
very different condition and requires specific treatment.
Why Does Lymphedema Occur?
Cancer therapy can damage the lymphatic system. The lymph system cannot remove the fluid it normally does from the tissue. This damage can slow the movement of lymph fluid in part of the body, causing fluid to build up. The extra fluid can cause swelling, often in the arms, legs, chest, face, and genitals. Slow movement of the lymph fluid also decreases the immune function of the lymph nodes and the amount of oxygen and nutrients reaching your body tissues.
Risk Factors for Lymphedema
After cancer treatment, a lifelong risk exists of developing lymphedema. Lymphedema may develop when the cancer is treated, after weeks, months or many years, or not at all. If you experience swelling after cancer therapy, see a health care professional right away.
Some common risk factors include:
- Radiation to the breast, or to lymph nodes in the armpit, under the breast, or under the collarbone
- Drainage or wound complications
- Cording: a web of thick, rope-like structures under the skin of your inner arm
- Formation of a “seroma” – a pocket of clear fluid that sometimes develops after surgery, after the drains have been removed
- Active cancer
- Any weight gain or being overweight
- A family history of lymphedema-related conditions
- Trauma in an at-risk arm or leg, such as an injection or having a blood sample taken
- Chronic skin disorders and inflammation
- High blood pressure
- Sedentary lifestyle
- Surgery with removal of the lymph nodes in the armpit
- Radiation causing inflammation and fibrosis, or scarring, of the skin
For more on Managing Lymphedema, please download Melanoma Network of Canada’s
Managing Lymphedema for the Melanoma Patient Guide