Arteriovenous malformation simulating Kaposi's sarcoma (pseudo-Kaposi's sarcoma).

A patient whose condition was initially misdiagnosed as Kaposi's sarcoma involving the left foot received radiation therapy for that disorder. Subsequent examination yielded a correct diagnosis of arteriovenous (AV) malformation. Such cases of AV malformations with skin changes resembling Kaposi's sarcoma have been called pseudo-Kaposi's sarcoma. The clinicopathologic distinctions between Kaposi's sarcoma and pseudo-Kaposi's lesions are discussed. All patients suspected of having Kaposi's sarcoma, especially those younger than 30 years of age, should have careful evaluation for an unsuspected AV malformation.