So-called fibroepithelial polyps of the vagina exhibiting an unusual but uniform antigen profile characterized by expression of desmin and steroid hormone receptors but no muscle-specific actin or macrophage markers.

The nature of the atypical, often multinucleated stromal cells proliferating in the so-called fibroepithelial polyps of the vagina (FEPV) is obscure. The authors therefore investigated immunohistochemically four polyps of this type with a panel of monoclonal and polyclonal antibodies, including those directed against intermediate filaments, steroid hormone receptors, and macrophage antigens. The authors found that the atypical stromal cells of FEPV expressed vimentin, desmin, and receptors for estrogen and progesterone but lacked all the other markers studied. The homogenous antigen profile strongly suggests that FEPV form a disease entity whose characteristic cells are special hormone-sensitive stromal cells with a myoid component of differentiation. Morphologically similar stromal cells expressing steroid hormone receptors but lacking desmin were found in myxomatoid subepithelial regions of the vaginal wall and the cervix.