title: Primary umbilical endometrioma: Analyzing the pathogenesis of endometriosis from an unusual localization.
abstract: OBJECTIVE
  This report presents a rare case of symptomatic primary umbilical endometriosis and reviews the literature on the topic with the aim to clarify some questions on the origin of endometriosis.
  
  
  METHODS
  A 33-year-old woman with cyclic umbilical bleeding was found to have umbilical endometriosis. She had no history of pelvic or abdominal surgery. There was no past history of endometriosis or endometriosis-associated symptoms. An omphalectomy was performed after explorative laparoscopy to carefully inspect the abdominopelvic cavity and assess any coexisting pelvic endometriotic lesions. Histological examination confirmed the diagnosis of umbilical endometriosis.
  
  
  CONCLUSIONS
  Umbilical endometriosis is a rare but under-recognized phenomenon. Primary lesions are difficult to recognize, but probably represent an independent nosological entity. The possibility of endometriosis must be considered during the evaluation of an umbilical mass despite the absence of previous surgery. Complete excision and successive histology are highly recommended.
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital "P. Giaccone", Palermo, Italy. Electronic address: gloria.calagna83@gmail.com.
authors.forename: Gloria
authors.initials: G
authors.lastname: Calagna
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Perino
authors.affiliation: Department of General Surgery, Emergency and Organ Transplantation, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Chianetta
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Vinti
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Maria Margherita
authors.initials: MM
authors.lastname: Triolo
authors.affiliation: Department of Pathological Anatomy, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Rimi
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Gaspare
authors.initials: G
authors.lastname: Cucinella
authors.affiliation: Department of General Surgery, Emergency and Organ Transplantation, University Hospital "P. Giaccone", Palermo, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Agrusa
mesh_terms: D000328:Adult; D004715:Endometriosis / Q000209:etiology / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D035583:Rare Diseases / Q000209:etiology / Q000473:pathology / Q000601:surgery; D014472:Umbilicus / Q000601:surgery*
keywords: endometriosis; laparoscopy; primary umbilical endometriosis; umbilical endometrioma; umbilicus