Pseudo-Kaposi's sarcoma (Mali type).

ABSTRACT

A 75-year-old man presented with lesions on his right leg and on the dorsum of the penis, which had appeared 5 years ago following long distance travel. His right leg was swollen, and there was a dark-violet-colored, slightly elevated lesion extending to the thigh and penis. Histologic examination revealed thickening of the arteriolar walls and diffuse proliferation of the vascular structures surrounding the arterioles and dissecting the dermal collagen fibers. Immunohistochemical staining for Factor VIII R-A reacted positively with arteriolar endothelium, but was negative on thin-walled vascular spaces. Femoral angiography showed multiple fine arteriovenous (A-V) shunts especially at the one-third distal lower region of the right leg.