Aggressive angiomyxoma of the pelvioperineal region. Immunohistological and ultrastructural study of seven cases.

We describe seven cases of aggressive angiomyxoma of the pelvioperineal region. In three cases, we observed immunohistochemical signs of myoid differentiation in the tumor cells. In one of these cases, we could confirm the myoid differentiation at the ultrastructural level. The other four cases were devoid of this differentiation. We further discuss the relationship of aggressive angiomyxoma to the recently described angiomyofibroblastoma of the vulva.