Female New-Born with Undifferentiated Sarcoma Defined by Bcor-Ccnb3 Fusion Transcript

A female new-born presented with a sacrococcygeal mass with spinal cord compression. A preliminary histologic diagnosis determined a small round blue cell tumor and immunohistochemical results discarded neuroblastoma, rhabdomyosarcoma, rhabdoid tumor, Ewing or peripheral neuroectodermal tumor (PNET). The results obtained by SNPa showed a chromosome Xp11.4 deletion of 0.9 Mb, where the BCOR gene is located. RT-PCR did not detect the ETV6-NTRK3 or EWSR1-FLI1 fusion, but did reveal the presence of the BCOR-CCNB3 fusion transcript, recently reported in some undifferentiated sarcomas, establishing the diagnosis of “Ewing-like” sarcoma. Analysis of CCNB3 expression by immunohistochemistry showed …