Extraorbital Giant Cell Angiofibroma

Overview

We describe a case of giant cell angiofibroma (GCA) in extraorbital location. A 47-year-old mandeveloped a subcutaneous tumor on the forearm, which measured 6 cm in diameter and was welldemarcated. Histologically, small-sized vessels similar to arterioles, sometimes with a hyalinizedwall, were regularly distributed throughout the tumor tissue. Lesional cells were oval and spindlein shape with pale eosinophilic cytoplasm and plump nuclei with clumped chromatin. In addition,larger bizarre cells with lobulated hyperchromatic nucleus were randomly admixed. Areas witha sieve-like pattern contained small slit-like spaces or larger pseudocystic spaces lined by tumorcells with an admixture of bizarre cells. Both mononuclear and bizarre lesional cells expressedstrongly and diffusely vimentin and CD34. Negative reactions were with cytokeratins, bcl-2, desmin,actin, VWF, S100, a-1-antitrypsin, CD99, lysozyme and FXIIIa. Our finding confirms that GCAis a benign neoplasm not necessarily confined to orbital location. The patient did well withoutrecurrence after 13 months of follow-up.

Key words:
giant cell angiofibroma - CD34 - soft tissue tumor