CONGENITAL HEMANGIOPERICYTOMA OF THE SKIN

A 5-month-old white boy had a pinhead red spot on his left malleolar r egion since birth. His mother noted progressive growth and, when he wa s first examined, the lesion measured 30x25x20 mm in size, had a pyram idal shape, covered by erythematous and smooth skin, with teleangiecta sia. The tumor was soft on palpation and movable over the deeper struc tures (Fig. 1a). X-ray examination revealed no bone abnormalities at t hat time, Just before the programmed incisional biopsy, the patient ha d a febrile episode due to upper respiratory tract viral infection dur ing which the tumor became ulcerated, bleeding and painful (Rig. 1b), As the bleeding was constant the lesion was surgically excised, at whi ch time the whole gelatinous mass was easily detached from the aponeur otic structures (Fig. 1c). The tumor measured 36x31x30 mm and had a wh itish, smooth cut surface crossed by small blood vessels. Histopatholo gic examination revealed a tumor mass extending from the mid dermis to the subcutaneous fat and composed of tightly packed fusiform cells in close opposition with lined vascular channels (Fig. 2a), There were a typical areas and mitotic figures were frequently seen. A reticulin pr eparation showed a dense network surrounding vessels and pericytes. Th e vessels branched in a staghorn configuration (Fig. 2b). The immunope roxidase technique with monoclonal antibody anti-factor VIII was posit ive in the endothelial cells surrounded by tumor cells (Fig. 2c). Seve n months after surgery the patient returned with a painful subcutaneou s mass on the upper third of his left leg that was adherent to the tib ial bone. X-ray examination disclosed osteolytic lesions at the tibial base and destruction of the peroneal head (Fig. 3). The patient was s ubmitted to radiotherapy, amputation of the left lower limb in the mid dle portion of the thigh and chemotherapy. He is clinically well 3 yea rs after treatment.