It is vital for lymphedema patients to be aware of the symptoms of infection and to seek immediate treatment, since recurrent infections or cellulitis, in addition to their inherent danger, further damage the lymphatic system and set up a vicious circle.In rare cases, lymphedema may lead to a form of cancer called lymphangiosarcoma, although the mechanism of carcinogenesis is not understood. Lymphedema-associated lymphangiosarcoma is called Stewart-Treves syndrome. Lymphangiosarcoma most frequently occurs in cases of long-standing lymphedema. The incidence of angiosarcoma is estimated to be 0.45% in patients living five years after radical mastectomy. Lymphedema is also associated with a low grade form of cancer called retiform hemangioendothelioma (a low grade angiosarcoma).Lymphedema can be disfiguring, and may result in a poor body image, which can cause psychological distress. Complications of lymphedema can cause difficulties in activities of daily living. Causes
Lymphedema may be inherited (primary) or caused by injury to the lymphatic vessels (secondary). Lymph node damage
It is most frequently seen after lymph node dissection, surgery and/or radiation therapy, in which damage to the lymphatic system is caused during the treatment of cancer, most notably breast cancer. In many patients with cancer, this condition does not develop until months or even years after therapy has concluded. Lymphedema may also be associated with accidents or certain diseases or problems that may inhibit the lymphatic system from functioning properly. In tropical endemic areas of the world, a common cause of secondary lymphedema is filariasis, a parasitic infection.
The first signs may be subjective observations such as a feeling of heaviness in the affected extremity. These may be symptomatic of early-stage lymphedema where accumulation of lymph is mild and not detectable by changes in volume or circumference. As lymphedema progresses, definitive diagnosis is commonly based upon an objective measurement of differences between the affected or at-risk limb at the opposite unaffected limb, e.g. in volume or circumference. No generally accepted criterion is definitively diagnostic, although a volume difference of 200 ml between limbs or a 4-cm difference (at a single measurement site or set intervals along the limb) is often used. Bioimpedance measurement (which measures the amount of fluid in a limb) offers greater sensitivity than existing methods.Chronic venous stasis changes can mimic early lymphedema, but the changes in venous stasis are more often bilateral and symmetric. Lipedema can also mimic lymphedema, however lipedema characteristically spares the feet beginning abruptly at the medial malleoli (ankle level). As a part of the initial work-up before diagnosing lymphedema, it may be necessary to exclude other potential causes of lower extremity swelling such as kidney failure, hypoalbuminemia, congestive heart-failure, protein-losing nephropathy, pulmonary hypertension, obesity, pregnancy and drug-induced edema. Classification
According to the Fifth WHO Expert Committee on Filariasis the most common method of classification of lymphedema is as follows: (The same classification method can be used for both primary and secondary lymphedema)
The International Society of Lymphology (ISL) Staging System is based solely on subjective symptoms, making it prone to substantial observer bias.