Alveolar soft part sarcoma of the vagina: an immunohistochemical and electron microscopic study.

Alveolar soft part sarcoma is a soft tissue neoplasm of unknown histogenesis which has a distinctive morphology. It is a relatively rare tumor with approximately 200 cases described in the literature. Only two cases have previously been reported as occurring in the vagina. The purpose of this paper is to report the third case of alveolar soft part sarcoma occurring in the vagina and to emphasize the role of electron microscopy in the differential diagnosis.