This clear fluid comes from the blood and carries disease-fighting cells throughout the body. Lymph also contains proteins and salts removed from the tissues. When the lymph nodes are removed, injured, or blocked, fluid builds up in the tissues. Lymphedema can be hereditary or caused by infection, but most often it occurs after surgery or radiation therapy for cancer. More than 400,000 American women are living with this problem.
Hereditary lymphedema can affect one or all limbs and sometimes other parts of the body.
It may be present at birth, or it might appear later in life. The cause is often unknown, but abnormalities of the lymph system seem to be responsible for some cases. Acquired lymphedema occurs after surgery, radiation therapy, infection, or injury. Surgical operations that require removal of lymph nodes greatly increase the risk for lymphedema. Swelling can occur immediately or weeks, months, or even many years after such surgery.