title: Ovarian cancer arising in endometrioid cysts: ultrasound findings.
abstract: OBJECTIVE
  To describe sonographic characteristics of malignant transformation in endometrioid cysts.
  
  
  METHODS
  Women with a histological diagnosis of ovarian endometrioid cysts, borderline tumors arising in endometrioid cysts and carcinoma arising in endometrioid cysts, preoperatively examined sonographically, were included in this retrospective study. Gray-scale and Doppler ultrasound characteristics of the endometrioid cysts were compared with those of the borderline tumors and primary cancers arising in endometrioid cysts. The performance of an experienced examiner in classifying the masses was also assessed.
  
  
  RESULTS
  Of 324 cases collected for the study, 309 (95.3%) lesions were classified as endometrioid cysts, four (1.2%) as borderline tumors arising in endometrioid cysts and 11 (3.4%) as carcinoma arising in endometrioid cysts. Women with malignant findings (borderline ovarian tumors and cancers) were older (median age 52 (range, 28-79) years) than those with benign endometrioid cysts (median age 34 (range, 18-76) years) (P<0.0001), and the prevalence of postmenopausal status was significantly higher in malignant cases. All (15/15) malignant tumors vs. 16% (50/309) of benign tumors were characterized by the presence of solid tissue (P<0.0001). The prevalence of solid tissue with positive Doppler signals was higher in malignant tumors (100%) than in benign cysts (7.8%) (P<0.0001). Papillary projections were a more frequent sonographic feature among malignant lesions (86.7%) than among benign endometrioid cysts (11.3%) (P<0.0001); power Doppler signals were detected within the projections in 92.3% and 37.1% of malignant and benign lesions, respectively. The examiner correctly diagnosed 94.8% (293/309) of benign lesions as benign and 93.3% (14/15) of malignant lesions as malignant. The risk estimation of the examiner was 'uncertain' in three (20%) and 'probably/certainly malignant' in 12 (80%) of 15 malignant cases.
  
  
  CONCLUSIONS
  Borderline tumors and carcinomas arising in endometrioid cysts show a vascularized solid component at ultrasound examination.
authors.affiliation: Department of Obstetrics and Gynecology, Catholic University, Rome, Italy. atesta@rm.unicatt.it
authors.forename: A C
authors.initials: AC
authors.lastname: Testa
authors.forename: D
authors.initials: D
authors.lastname: Timmerman
authors.forename: C
authors.initials: C
authors.lastname: Van Holsbeke
authors.forename: G F
authors.initials: GF
authors.lastname: Zannoni
authors.forename: S
authors.initials: S
authors.lastname: Fransis
authors.forename: P
authors.initials: P
authors.lastname: Moerman
authors.forename: V
authors.initials: V
authors.lastname: Vellone
authors.forename: F
authors.initials: F
authors.lastname: Mascilini
authors.forename: A
authors.initials: A
authors.lastname: Licameli
authors.forename: M
authors.initials: M
authors.lastname: Ludovisi
authors.forename: A
authors.initials: A
authors.lastname: Di Legge
authors.forename: G
authors.initials: G
authors.lastname: Scambia
authors.forename: G
authors.initials: G
authors.lastname: Ferrandina
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018269:Carcinoma, Endometrioid / Q000000981:diagnostic imaging* / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D004715:Endometriosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D008875:Middle Aged; D010048:Ovarian Cysts / Q000000981:diagnostic imaging* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D012189:Retrospective Studies; D018615:Ultrasonography, Doppler, Color; D055815:Young Adult