title: Use of risk of malignancy index to indicate frozen section analysis in the surgical care of women with ovarian tumors.
abstract: OBJECTIVE
  To evaluate the importance of the risk of malignancy index (RMI) in the decision to perform frozen section analysis among women with ovarian tumors.
  
  
  METHODS
  A retrospective study was conducted in 11 centers in the Netherlands. Women who underwent surgical treatment of an ovarian mass with unknown histology between January 2005 and September 2009 were included. The RMI was calculated retrospectively. Frozen section analysis and RMI values were assessed for patients with benign, borderline, and malignant ovarian tumors on final histopathology.
  
  
  RESULTS
  Overall, 670 women were included. Frozen sections were performed in 323 (48.2%) patients, of whom 206 (63.8%) were diagnosed with benign ovarian tumors, 55 (17.0%) with borderline tumors, and 62 (19.2%) with malignant tumors. Overall, 109 (16.3%) women had an RMI below 20, 106 (97.2%) of whom had benign histology results. Among 235 patients with an RMI over 100, 3 (1.3%) postmenopausal women had malignancies that were missed because frozen sections were not performed.
  
  
  CONCLUSIONS
  Women with an RMI below 20 have a low risk of malignancy and therefore do not require frozen section analysis. Postmenopausal women with an RMI greater than 100 should be referred to centers where frozen sections can be performed, and proper facilities and expertise are available to perform staging procedures if necessary.
authors.affiliation: Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, Netherlands. Electronic address: sabine.vandenakker@radboudumc.nl.
authors.forename: Petronella A J
authors.initials: PA
authors.lastname: van den Akker
authors.affiliation: Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Petra L M
authors.initials: PL
authors.lastname: Zusterzeel
authors.affiliation: Department of Obstetrics and Gynecology, Rijnstate Hospital, Arnhem, Netherlands.
authors.forename: Anette L
authors.initials: AL
authors.lastname: Aalders
authors.affiliation: Department of Obstetrics and Gynecology, Canisius-Wilhelmina Hospital, Nijmegen, Netherlands.
authors.forename: Marc P L M
authors.initials: MP
authors.lastname: Snijders
authors.affiliation: Department of Obstetrics and Gynecology, Gelderse Vallei Hospital, Ede, Netherlands.
authors.forename: Rahul A K
authors.initials: RA
authors.lastname: Samlal
authors.affiliation: Department of Obstetrics and Gynecology, Bernhoven Hospital, Uden, Netherlands.
authors.forename: Jos H A
authors.initials: JH
authors.lastname: Vollebergh
authors.affiliation: Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Kirsten B
authors.initials: KB
authors.lastname: Kluivers
authors.affiliation: Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Leon F A G
authors.initials: LF
authors.lastname: Massuger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005629:Frozen Sections; D006801:Humans; D008875:Middle Aged; D009426:Netherlands; D010051:Ovarian Neoplasms / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D055815:Young Adult
keywords: Frozen section analysis; Ovarian tumors; Risk of malignancy index