Clinical challenge: cutaneous Kaposi's sarcoma of the lower extremity.

Kaposi's sarcoma (KS) typically presents as multiple bilateral cutaneous patches or plaques of the lower extremities. This malignancy, however, can evolve with atypical presentation masquerading as a chronic wound. Lesions can mimic venous stasis ulcers, arterial insufficiency, vascular ulcers or chronic-infected wounds. With acquired immune deficiency syndrome (AIDS)-associated KS, lesions are even more widespread, and can affect the respiratory tract, lymph nodes, gastrointestinal tract, spleen, liver and, rarely, bone. As the initial diagnosis of KS is generally determined clinically, a high index of suspicion is necessary for all patients with a known or suspected history of HIV/AIDS. Tissue biopsy with histological analysis is essential for all wound types in this patient subset, regardless of wound presentation. The purpose of this report is to review the pathogenesis as well as the typical and atypical presentations of KS with an example of a diagnostic dilemma.