Uterine Tumor Resembling Ovarian Sex Cord Tumor: A Distinct Entity Characterized by Recurrent NCOA2/3 Gene Fusions.

Uterine tumor resembling ovarian sex-cord tumor (UTROSCT) is a rare and distinctive neoplasm of unclear histogenesis, and uncertain malignant potential. These neoplasms morphologically resemble sex-cord stromal tumors of the ovary, and possess a polyphenotypic immunophenotype. Their molecular pathogenesis has yet to be elucidated; notably, however, tumors lack alterations found in other uterine tumors bearing sex-cord-like differentiation, such as endometrial stromal sarcoma.

Novel EPC1 gene fusions in endometrial stromal sarcoma.

Endometrial stromal sarcoma encompasses a heterogeneous group of uterine mesenchymal neoplasms, which are currently divided into low-grade and high-grade subtypes. Low-grade endometrial stromal sarcoma is morphologically bland; molecularly, these tumors frequently contain JAZF1-SUZ12, JAZF1-PHF1, and EPC1-PHF1 fusions. In contrast, high-grade endometrial stromal sarcoma is characterized by morphologically undifferentiated neoplasms with high-grade nuclear features; these tumors likewise appear to be genetically diverse with YWHAE-NUTM2 and ZC3H7B-BCOR representing the most frequent gene fusions.