Lymphedema is a set of pathologic conditions that are characterized by the
regional accumulation of excessive amounts of interstitial protein-rich flu
id. These occur as a result of an imbalance between the demand for lymphati
c flow and the capacity of the lymphatic circulation. Lymphedema can result
from either primary or acquired (secondary) disorders. In this review, the
pathophysiology, classification, natural history, differential diagnosis,
and treatment of lymphedema are discussed.