[Primary uterine and vulvar Ewing's sarcoma/peripheral neuroectodermal tumors in children: two unusual locations].

Two genital cases of Ewing's sarcoma/peripheral neuroectodermal tumor in 14 and 15 year old teenagers are reported. They arose in uteri and vulva, as small round cell tumors with some rosette-like formations and intense membranous immunoreactivity for CD99. The EWS/FLI-1 transcript was present in the vulvar tumor. Under chemotherapy, uterine tumor outcome was fatal within 9 months. The vulvar lesion was treated by surgery and chemotherapy, without relapse after 7 months. Likewise to these 2 cases, the literature seems to indicate different prognosis for uterine and vulvar tumors.