Soft tissue Ewing sarcoma--peripheral primitive neuroectodermal tumor with atypical clear cell pattern shows a new type of EWS-FEV fusion transcript.

:This study describes a new case of Ewing sarcoma (ES)-peripheral primitive neuroectodermal tumor (pPNET) with unusual phenotype and fusion gene structure. The tumor located in the inguinal area of a 15-year-old boy showed a highly aggressive behavior with hematogenous metastases after intensive chemotherapy and bone marrow transplant, causing death 28 months after diagnosis. The tumor displayed a clear cell pattern, and several neuroectodermal markers proved positive both in the original tumor and in xenografts. This neuroectodermal character was confirmed by electron microscopy. Moreover, cytogenetically the tumor has an unusual chromosomal rearrangement, t(2;22)(q13;q22,t(3;18)(p21;q23); representing a new EWS-FEV fusion type in which exon 7 of EWS gene is fused with exon 2 of FEV gene. This is the third published study of an ES-pPNET showing EWS-FEV fusion described, but it is the first study of a tumor with the aforementioned fusion points. These findings support the genetic and morphologic heterogeneity existing within the group of ES-pPNET tumors.

Llombart-Bosch A ，Pellín A ，Carda C ，Noguera R ，Navarro S ，Peydró-Olaya A ... -  《diagnostic molecular pathology》

Atypical pleomorphic extraosseous ewing tumor/peripheral primitive neuroectodermal tumor with unusual phenotypic/genotypic profile.

Navarro S ，Noguera R ，Pellín A ，López-Guerrero JA ，Roselló-Sastre E ，Cremades A ，Llombart-Bosch A ... -  《diagnostic molecular pathology》

Peripheral primitive neuroectodermal tumor of the ovary confirmed by CD99 immunostaining, karyotypic analysis, and RT-PCR for EWS/FLI-1 chimeric mRNA.

Kawauchi S ，Fukuda T ，Miyamoto S ，Yoshioka J ，Shirahama S ，Saito T ，Tsukamoto N ... -  《AMERICAN JOURNAL OF SURGICAL PATHOLOGY》

[Case report of a subcutaneous peripheral primitive neuroectodermal tumor].

Cabrera R ，Sánchez P ，Rodríguez MA 《-》

Olfactory neuroblastoma is a peripheral primitive neuroectodermal tumor related to Ewing sarcoma.

Sorensen PH ，Wu JK ，Berean KW ，Lim JF ，Donn W ，Frierson HF ，Reynolds CP ，López-Terrada D ，Triche TJ ... -  《-》