title: A subserosal uterus-like mass presenting after a sliding hernia of the ovary and endometriosis: a rare entity with a discussion of the histogenesis.
abstract: OBJECTIVE
  To report the first case of a subserosal uterus-like mass.
  
  
  METHODS
  Case report.
  
  
  METHODS
  A community-based hospital.
  
  
  METHODS
  A 44-year-old nulliparous woman who complained of a left inguinal mass had a medical history that was notable for two features. One was left oophorectomy for a sliding hernia at 10 months of age; the other was endometriosis at the oophorectomy site at 26 years of age.
  
  
  METHODS
  Tumorectomy.
  
  
  METHODS
  Not applicable.
  
  
  RESULTS
  Pathologic examination demonstrated that this subserosal mass mimicked a miniature uterus with a leiomyomatous lesion.
  
  
  CONCLUSIONS
  As of September 2010, 23 cases of uterus-like mass had been reported. Three pathologic theories of uterus-like mass have been proposed: [1] congenital anomaly theory, [2] metaplasia theory, and [3] heterotopia. The pathogenesis of this rare entity is currently under debate. Most uterus-like masses have been connected to the genital organs (75.0%) and associated with endometriosis (50.0%). In the present case, the uterus-like mass developed at the surgical scar site of oophorectomy for a sliding hernia and a tumorectomy for endometriosis. We review the literature and discuss the theories regarding the histogenesis of uterus-like mass.
authors.affiliation: The Pathology Division, Clinical Laboratories, National Hospital Organization Tokyo Medical Center, Tokyo, Japan. aseki@ntmc.hosp.go.jp
authors.forename: Atsuko
authors.initials: A
authors.lastname: Seki
authors.forename: Arafumi
authors.initials: A
authors.lastname: Maeshima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Junichi
authors.initials: J
authors.lastname: Shiraishi
authors.forename: Yuya
authors.initials: Y
authors.lastname: Murata
authors.forename: Hiroharu
authors.initials: H
authors.lastname: Arai
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kubochi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kuramochi
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D004715:Endometriosis / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006547:Hernia / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008679:Metaplasia / Q000453:epidemiology / Q000209:etiology; D010049:Ovarian Diseases / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D012704:Serous Membrane / Q000473:pathology; D014591:Uterine Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D014599:Uterus / Q000473:pathology* / Q000601:surgery