title: Endometrial adenocarcinoma arising from endometriosis of the rectosigmoid colon.
abstract: BACKGROUND
  Only 21.3% of cases of malignant transformation of endometriosis occur at extragonadal pelvic sites. Forty cases of endometriosis-associated intestinal tumors are reported in the literature. Of these, 17 cases are primary adenocarcinomas arising in the rectosigmoid colon. In 8 of the 17 case reports the patients were using unopposed estrogen replacement therapy.
  
  
  METHODS
  The patient had previously undergone a total abdominal hysterectomy and bilateral salpingo-oophorectomy for deeply infiltrating rectovaginal endometriosis, and was using estrogen replacement therapy. She presented with rectal bleeding 12 years later, and a polyp was detected arising from the sigmoid colon. A biopsy detected malignant transformation of endometriosis to adenocarcinoma.
  
  
  CONCLUSIONS
  This is the ninth case of a patient with this condition reported in the literature.
authors.affiliation: The Royal Surrey County Hospital, Surrey, United Kingdom. kjones@rschguildford.freeserve.co.uk
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Jones
authors.forename: Eoghan
authors.initials: E
authors.lastname: Owen
authors.forename: Ann
authors.initials: A
authors.lastname: Berresford
authors.forename: Christopher
authors.initials: C
authors.lastname: Sutton
mesh_terms: D000230:Adenocarcinoma / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D001706:Biopsy; D016889:Endometrial Neoplasms / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D004715:Endometriosis / Q000150:complications*; D005260:Female; D006801:Humans; D007813:Laparotomy; D008875:Middle Aged; D012002:Rectal Diseases / Q000150:complications*; D012810:Sigmoid Diseases / Q000150:complications*