title: Evaluation of fluorescence in-situ hybridization in monomorphic endometrial stromal neoplasms and their histological mimics: a review of 49 cases.
abstract: OBJECTIVE
  To perform a population-based review of monomorphic endometrial stromal tumours and their histological mimics presenting over a 20-year period, including an evaluation of fluorescence in-situ hybridization (FISH) for the JAZF1 and YWHAE breakaparts.
  
  
  RESULTS
  Forty-nine tumours were examined, comprising 13 histological mimics and 36 endometrial stromal tumours [six stromal nodules (ESNs), 25 low-grade stromal sarcomas (ESSs), and five monomorphic undifferentiated sarcomas (mUESs)]. Nine ESSs showed variant histological patterns, including smooth muscle, sex cord-like/glandular, fibrous or rhabdoid differentiation. Three ESSs were initially misclassified as benign uterine lesions, and, conversely, three benign mimics were originally reported as ESSs. One mUES showed a prominent pseudopapillary pattern. Fluorescence in-situ hybridization demonstrated JAZF1 breakaparts in five of six ESNs and 16 of 25 ESSs; however, only three of nine ESS variants were positive. YWHAE breakaparts were present in four of five mUESs. Analysis of a subsequent metastasis in the YWHAE breakapart-negative mUES demonstrated a YWHAE deletion. None of the histological mimics was positive in FISH analysis. Diffuse cyclin D1 expression was restricted to mUESs in this series.
  
  
  CONCLUSIONS
  Endometrial stromal neoplasms continue to present diagnostic difficulty. Fluorescence in-situ hybridization analysis is helpful in distinguishing stromal tumours from their histological mimics and in distinguishing ESS from mUES.
authors.affiliation: Department of Histopathology, King Edward Memorial Hospital, Perth, WA, Australia; School of Women's and Infants Health, University of Western Australia, Perth, WA, Australia.
authors.forename: Colin J R
authors.initials: CJ
authors.lastname: Stewart
authors.forename: Yee C
authors.initials: YC
authors.lastname: Leung
authors.forename: Ashleigh
authors.initials: A
authors.lastname: Murch
authors.forename: Joanne
authors.initials: J
authors.lastname: Peverall
mesh_terms: D048948:14-3-3 Proteins / Q000032:analysis; D000328:Adult; D000368:Aged; D001315:Australia; D056970:Co-Repressor Proteins; D019938:Cyclin D1 / Q000302:isolation & purification; D004268:DNA-Binding Proteins; D003937:Diagnosis, Differential; D016889:Endometrial Neoplasms / Q000175:diagnosis* / Q000473:pathology; D036821:Endometrial Stromal Tumors / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis; D014178:Translocation, Genetic / Q000235:genetics
chemical_list: D048948:14-3-3 Proteins; D056970:Co-Repressor Proteins; D004268:DNA-Binding Proteins; C430460:JAZF1 protein, human; D009363:Neoplasm Proteins; C482983:YWHAE protein, human; D019938:Cyclin D1
keywords: JAZF1; YWHAE; endometrial stromal tumour; fluorescence in-situ hybridization; immunohistochemistry; sarcoma