Primary vulvar and vaginal extraosseous Ewing's sarcoma/peripheral neuroectodermal tumor: diagnostic confirmation with CD99 immunostaining and reverse transcriptase-polymerase chain reaction.
Two cases of extraosseous Ewing's sarcoma/peripheral neuroectodermal tumor arising in unusual, superficial sites are reported. One tumor involved the vaginal wall of a 35-year-old woman, and the other neoplasm arose in the dermis of the vulva in a 28-year-old woman. The tumors showed characteristic microscopic features of Ewing's sarcoma/peripheral neuroectodermal tumor with nodular monotonous proliferations of undifferentiated, small, round, hyperchromatic cells with a low mitotic index. Rare rosette-like formations were apparent only in the vulvar neoplasm. The tumors displayed intense immunoreactivity in a membranous pattern for CD99, the cell surface glycoprotein encoded by the MIC2 gene. Genetically, the tumors expressed the EWS/FLI-1 chimeric transcript, derived from the t(11;22)(q24;q12) chromosomal translocation. Both patients had localized disease treated with wide local excision; one received postoperative chemotherapy, and the other received chemotherapy and radiotherapy. To date, 18 and 19 months after diagnosis, neither patient has had clinical evidence of local recurrence or metastasis. To our knowledge, these are the first reported cases of vaginal and vulvar Ewing's sarcoma/peripheral neuroectodermal tumor, confirmed with molecular genetic analysis, in the English literature.
Vang
R
R
Department of Pathology, University of Texas Medical School, Houston, USA.
Taubenberger
J K
JK
Mannion
C M
CM
Bijwaard
K
K
Malpica
A
A
Ordonez
N G
NG
Tavassoli
F A
FA
Silver
S A
SA
D000071443:12E7 Antigen; D000328:Adult; D015703:Antigens, CD / Q000032:analysis*; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015815:Cell Adhesion Molecules / Q000032:analysis*; D002880:Chromosomes, Human, Pair 11; D002892:Chromosomes, Human, Pair 22; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017599:Neuroectodermal Tumors / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy; D011878:Radiotherapy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012512:Sarcoma, Ewing / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy; D013514:Surgical Procedures, Operative; D014178:Translocation, Genetic; D014625:Vaginal Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy; D014846:Vulvar Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy
D000071443:12E7 Antigen; D015703:Antigens, CD; D000970:Antineoplastic Agents; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules