Primary vaginal Ewing sarcoma: case report and review of the literature.

Ewing sarcoma (ES) and primitive neuroectodermal tumor (PNET) are round-cell sarcomas with varying degrees of neuroectodermal differentiation; they are considered members of the same family of tumors based on their common genetic profile. ES/PNET are very infrequent in the female genital tract, the vagina being the rarest gynecological location, with 7 cases reported to date. The authors present a case of vaginal ES/PNET with typical morphological and immunohistochemical features. EWS gene rearrangement was demonstrated by fluorescent in situ hybridization analysis. Of the 7 previously reported cases, only 2 have molecular confirmation. The age at presentation for vaginal ES/PNET is slightly higher than that for these neoplasms in bone and soft tissues, with only 1 reported patient younger than 30 years. The outcome seems to be similar to that of other superficially sited ES/PNET and more favorable than for those observed in the more typical locations. However, the currently available data are limited, and therefore, a larger number of cases is necessary to draw any firm conclusions.