 The BCOR-CCNB3 fusion gene, resulting from a chromosome X paracentric inversion, was recently described in translocation-negative 'Ewing-like' sarcomas arising in bone and soft tissue.     ///    Using whole transcriptome paired-end RNA sequencing (RNA-seq) we unexpectedly identified BCOR-CCNB3 fusion transcripts in an undifferentiated spindle-cell sarcoma.     ///    All patients with BCOR-CCNB3 sarcoma were males diagnosed in mid childhood (7-13 years of age).     ///    BCOR-CCNB3 fusions are frequent in undifferentiated sarcomas of male children..     ///    Five additional undifferentiated sarcomas with BCOR-CCNB3 fusions were identified in a series of 42 pediatric and adult unclassified sarcomas.     ///    "This study adds to recent reports on the clinicopathologic spectrum of BCOR-CCNB3 fusion-positive sarcomas, a newly emerging entity within the undifferentiated unclassified sarcoma category and describes a simple RT-PCR assay that in conjunction with CCNB3 immunohistochemistry can be useful in diagnosing these tumors. "