title: Peripheral primitive neuroectodermal tumor of the ovary confirmed by CD99 immunostaining, karyotypic analysis, and RT-PCR for EWS/FLI-1 chimeric mRNA.
abstract: We report a case of peripheral primitive neuroectodermal tumor (pPNET), which belongs to the PNET/Ewing's sarcoma family, arising in the left ovary of a 29-year-old woman. Microscopically, the tumor was composed of solid nests and sheets of monotonous, primitive, small round cells with a few rosettes, making it difficult to distinguish from small cell carcinoma of the ovary. Immunohistochemically, the tumor cells showed intense cell-membranous immunoreactivity for MIC2 protein (CD99). A short-term cell culture and karyotypic analysis revealed the tumor to possess a balanced t(11;22)(q24;q12) chromosomal translocation that is highly specific for tumors of the PNET/Ewing's sarcoma family. In addition, EWS/FLI-1 chimeric mRNA that originated from the characteristic chromosomal translocation was detected by reverse transcription-polymerase chain reaction. These results confirmed the diagnostic validity of the present tumor being a pPNET, thus raising the possibility that in the past, pPNETs which have arisen in the ovary may have been mistakenly diagnosed as small cell carcinomas of the ovary.
authors.affiliation: Department of Pathology, National Kyushu Cancer Center, Fukuoka, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kawauchi
authors.forename: T
authors.initials: T
authors.lastname: Fukuda
authors.forename: S
authors.initials: S
authors.lastname: Miyamoto
authors.forename: J
authors.initials: J
authors.lastname: Yoshioka
authors.forename: S
authors.initials: S
authors.lastname: Shirahama
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: N
authors.initials: N
authors.lastname: Tsukamoto
mesh_terms: D000071443:12E7 Antigen; D000328:Adult; D015703:Antigens, CD / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000032:analysis; D015815:Cell Adhesion Molecules / Q000032:analysis*; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics; D005260:Female; D006801:Humans; D007621:Karyotyping; D018242:Neuroectodermal Tumors, Primitive / Q000737:chemistry / Q000175:diagnosis* / Q000235:genetics; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D010051:Ovarian Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000235:genetics; D051789:Proto-Oncogene Protein c-fli-1; D012333:RNA, Messenger / Q000032:analysis*; D012334:RNA, Neoplasm / Q000032:analysis; D034802:RNA-Binding Protein EWS; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012512:Sarcoma, Ewing / Q000737:chemistry / Q000175:diagnosis / Q000235:genetics; D014057:Tomography, X-Ray Computed; D014157:Transcription Factors / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics; D014407:Tumor Cells, Cultured
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; C106031:EWS-FLI fusion protein; D015514:Oncogene Proteins, Fusion; D051789:Proto-Oncogene Protein c-fli-1; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D034802:RNA-Binding Protein EWS; D014157:Transcription Factors