title: Sonographic assessment of non-malignant ovarian cysts: does sonohistology exist?
abstract: BACKGROUND
  Transvaginal ultrasound (TVU) is feasible and accurate in the differentiation between non-malignant and malignant ovarian abnormalities. However, despite the clinical relevance, the accuracy of TVU in the differentiation between the many different non-malignant cysts is unknown.
  
  
  METHODS
  Between 1992 and 2002, all women who had surgery at our centre because of a non-malignant ovarian cyst were included prospectively in this study. The sonographic characteristics as well as the expected histological diagnosis (the 'sonohistological diagnosis') were evaluated pre-operatively. This diagnosis was compared with the histopathological diagnosis, and diagnostic parameters [with 95% confidence interval (CI)] of the sonohistological diagnosis were calculated. Logistic models, with the sonographic characteristics as variables, were constructed for each histopathological diagnosis.
  
  
  RESULTS
  A total of 406 women were included consecutively. The overall diagnostic accuracy of the sonohistological diagnosis was 60% (95% CI 0.56-0.65). Only in cases of simple ovarian cysts did the diagnostic accuracy of the respective logistic model exceed that of the sonohistological diagnosis (0.88 versus 0.81, P < 0.01). The diagnostic accuracy of the sonohistological diagnosis for endometriotic and dermoid ovarian cysts was significantly better compared with the respective logistic model (0.84 versus 0.71, P < 0.01 and 0.87 versus 0.82, P = 0.03, respectively).
  
  
  CONCLUSIONS
  In approximately half of the non-malignant ovarian cysts, TVU is capable of distinguishing between the different histopathological diagnoses of non-malignant ovarian masses. Only in the diagnosis of simple ovarian cysts might use of the logistic models be helpful.
authors.affiliation: Department of Gynaecology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
authors.forename: C D
authors.initials: CD
authors.lastname: de Kroon
authors.forename: H A G M
authors.initials: HA
authors.lastname: van der Sandt
authors.forename: J C
authors.initials: JC
authors.lastname: van Houwelingen
authors.forename: F W
authors.initials: FW
authors.lastname: Jansen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003884:Dermoid Cyst / Q000000981:diagnostic imaging / Q000473:pathology; D003937:Diagnosis, Differential; D004715:Endometriosis / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D016017:Odds Ratio; D010048:Ovarian Cysts / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D011300:Preoperative Care; D011446:Prospective Studies; D014463:Ultrasonography / Q000592:standards