A specific FISH assay was developed to detect the novel t(X;17) translocation in formalin-fixed paraffin-embedded material, and resulted in identification of an additional low-grade ESS case positive for the MBTD1-CXorf67 fusion among 25 uterine stromal tumors [14 ESS and 11 undifferentiated endometrial sarcomas (UESs)] that were negative for JAZF1 and YWHAE rearrangements.     ///    "A specific FISH assay was developed to detect the novel t(X;17) translocation in formalin-fixed paraffin-embedded material, and resulted in identification of an additional low-grade ESS case positive for the MBTD1-CXorf67 fusion among 25 uterine stromal tumors [14 ESS and 11 undifferentiated endometrial sarcomas (UESs)] that were negative for JAZF1 and YWHAE rearrangements."    ///    The presence of the MBTD1-CXorf67 fusion transcript was validated in both cases using reverse-transcription polymerase chain reaction followed by Sanger sequencing.     ///    Gene expression profiles of seven ESS (including three with YWHAE and two with JAZF1 rearrangements) and four UES without specific chromosomal aberrations indicated clustering of tumors with MBTD1-CXorf67 fusion together with low-grade JAZF1-associated ESS.     ///    "Identification of a novel, recurrent MBTD1-CXorf67 fusion in low-grade endometrial stromal sarcoma.. "    ///    The chimeric MBTD1-CXorf67 fusion identifies yet another cytogenetically distinct subgroup of low-grade ESS and offers the opportunity to shed light on the functions of two poorly characterized genes. 