title: Clear cell adenocarcinoma arising in endometriosis of a previous episiotomy site.
abstract: BACKGROUND
  Malignant transformation of endometriosis in an episiotomy site is rare.
  
  
  METHODS
  A 42-year-old woman presented with a palpable mass, 2.5 cm in size, just inside the posterior commissure of the vagina, at the site of a previous episiotomy for a vaginal delivery. Three years previously, an endometriotic cyst had been excised at the same site, and the patient had been treated with a gonadotropin-releasing hormone analogue for 6 months. Biopsy revealed a clear cell adenocarcinoma arising in endometriosis. The patient underwent radical surgery alone without adjuvant therapy. At 10-month follow-up, there was no evidence of recurrence.
  
  
  CONCLUSIONS
  Patients who experience a recurrence of extragonadal endometriosis after prior therapy should be monitored carefully for malignant degeneration.
authors.affiliation: Department of Obstetrics and Gynecology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yong-Soon
authors.initials: YS
authors.lastname: Kwon
authors.forename: Joo-Hyun
authors.initials: JH
authors.lastname: Nam
authors.forename: Gawon
authors.initials: G
authors.lastname: Choi
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D000328:Adult; D004715:Endometriosis / Q000150:complications* / Q000209:etiology / Q000473:pathology; D004841:Episiotomy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007049:Iatrogenic Disease; D014846:Vulvar Neoplasms / Q000209:etiology* / Q000473:pathology / Q000601:surgery