title: Recent developments in uterine mesenchymal neoplasms.
abstract: Smooth muscle and endometrial stromal tumours represent the two most common uterine mesenchymal neoplasms that may present diagnostic dilemmas for the practising surgical pathologist. Recent changes in morphological and staging criteria, as well as the discovery of new immunohistochemical markers, have improved the diagnosis and classification of these tumours. We highlight the difficulty in distinguishing tumour cell necrosis from infarct-type necrosis and the limited utility of p16 immunohistochemical expression in the diagnosis of leiomyosarcoma. We also discuss the controversial use of mitotic activity and necrosis as prognostic factors in endometrial stromal sarcomas. Emerging genetic information has also greatly expanded our understanding of 'sarcomagenesis' in both tumour types and may provide insight into potential therapeutic targets for the treatment of leiomyosarcoma and endometrial stromal sarcomas, harboring MED12 (mediator complex subunit 12) mutations and recurrent gene rearrangements, respectively. In this review, we discuss the core updates in the diagnosis and classification of uterine leiomyosarcomas and endometrial stromal sarcomas, highlighting new and important molecular genetic findings that may drive pathogenesis.
authors.affiliation: Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Chiang
authors.forename: Esther
authors.initials: E
authors.lastname: Oliva
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D003937:Diagnosis, Differential; D036821:Endometrial Stromal Tumors / Q000145:classification / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D005260:Female; D050939:Gene Fusion; D015321:Gene Rearrangement; D006801:Humans; D007238:Infarction / Q000175:diagnosis; D007890:Leiomyosarcoma / Q000145:classification / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D056892:Mediator Complex / Q000235:genetics; D008938:Mitosis; D009154:Mutation; D009336:Necrosis / Q000175:diagnosis; D009367:Neoplasm Staging; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D011379:Prognosis; D014594:Uterine Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C460107:MED12 protein, human; D056892:Mediator Complex; D015514:Oncogene Proteins, Fusion; C576541:YWHAE-FAM22 fusion protein, human