RESUMO
ObjectiveTo understand the clinical and histopathologic diagnostic criteria for aneurysmal fibrous histiocytoma(AFH).MethodsThe clinical and histopathological features of 5 patients with AFH were retrospectively reviewed.ResultsThere were 3 males and 2 females in these patients.All the tumors clinically manifested as dark erythematous or brown nodules.Three cases had a recent history of rapid growth.The lesions were located on the limbs(n =3),or chest and lower mandible(n =2).Histopathological examination of skin biopsies showed typical features of dermatofibroma,accompanied by many irregular cleftlikeorcavernousblood-filledspaceswithnumeroushemosiderinpigmentsinallofthesecases.Immunohistochemically,the tumor cells were immunoreactive to vimentin and CD68 but negative for CD34 or CD31.Conclusions In view of a history of recent rapid growth,the presence of hemorrhagic pseudocysts and high vascularity,AFH should be differentiated from angiosarcoma and angiomatoid fibrous histiocytoma.