Contributor: Gordon K Klintworth
Ewing sarcoma (peripheral  neuroectodermal tumor, peripheral neuroepithelioma, PNET) is a specific malignant "small blue cell tumor" [blue cell tumor] neoplasm characterized by a specific chromosomal translocation between human chromosome 11 and 22 [ t(11;22)(q24;q12)]. A diagnosis of this chromosome translocation syndrome can be established on unfixed cells with a two color FISH technique. Wilm tumor reacts with antibodies to myogenin. The differential diagnosis includes other small "blue cell tumors", such as rhabdomyosarcoma, neuroblastoma, and peripheral primitive neuroectodermal tumor.