What is Lymphedema? Lymphedema is a chronic condition characterized by severe swelling that typically occurs in one of your arms or legs. It is caused by a blockage or compromise in your lymphatic system , which prevents lymph fluid from draining properly. As the protein-rich fluid builds up in the tissues, the limb begins to swell. While there is currently no cure, the condition can be effectively managed. It is most commonly caused by the surgical removal of or radiation damage to lymph nodes as a part of cancer treatment. Symptoms The swelling associated with lymphedema can range from mild, barely noticeable changes to extreme enlargement that makes using the affected limb difficult. Common clinical signs include: Swelling: Noticeable swelling in part or all of your arm or leg, often extending down into the fingers or toes. Heaviness: A persistent feeling of aching, tightness, or profound weight in the limb. ...