title: Should cut-off values of the risk of malignancy index be changed for evaluation of adnexal masses in Asian and Pacific populations?
abstract: BACKGROUND
  The risk of malignancy index (RMI) for the evaluation of adnexal masses is a sensitive tool in certain populations. The best cut off value for RMI 1, 2 and 3 is 200. The cut off value of RMI-4 to differentiate benign from malignant lesions is 450. Our aim was to evaluate the efficiency of four different malignancy indexes (RMI1-4) in a homogeneous population.
  
  
  METHODS
  We evaluated a total of 153 non-pregnant women with adnexal masses who did not have a history of malignancy and who were above 18 years of age.
  
  
  RESULTS
  A cut-off value of 250 for RMI-1 provided 95.9% inter-observer agreement, yielding 95.9% specificity, 93.5% negative predictive value, 75.0% sensitivity and 82.8% positive predictive value. A cut-off value of 250 for RMI-1 showed high performance in preoperative diagnosis of invasive malignant lesions than cut-off value of 200 in our population. A cut-off value of 350 for RMI-2 provided 94.5% inter-observed agreement, yielding 94.2% specificity, 93.4% negative predictive value, 75.0% sensitivity and 77.4% positive predictive value. RMI-2 showed the higher performance when the cut-off value was set at 350 in our population. A cut-off value of 250 provided 95.2% inter-observer agreement, yielding 95.0% specificity, 93.2% negative predictive value, 75.0% sensitivity, and 88.0% positive predictive value. RMI-3 showed the highest performance to diagnose malignant adnexal masses when the cut-off value was set at 250. In our study, RMI-4 showed similar statistical performance when the cut-off value was set at 400 [(Kappa: 0.684/p=0.000), yielding 93.8% inter-observer agreement, 93.4% specificity, 93.4% negative predictive value, 75.0% sensitivity, and 75.0% negative predictive value].
  
  
  CONCLUSIONS
  We showed successful utilization of RMIs in preoperative differentiation of benign from malignant masses. Many studies conducted in Asian and Pacific countries have reported different cut-off values as was the case in our study. We think that it is difficult to determine universally accepted cut-off values for RMIs for common use around the globe.
authors.affiliation: Department of Obstetrics and Gynaecology, Duzce University Faculty of Medicine, Duzce, Turkey E-mail : draliyavuzcan@yahoo.com.
authors.forename: Ali
authors.initials: A
authors.lastname: Yavuzcan
authors.forename: Mete
authors.initials: M
authors.lastname: Caglar
authors.forename: Emre
authors.initials: E
authors.lastname: Ozgu
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Ustun
authors.forename: Serdar
authors.initials: S
authors.lastname: Dilbaz
authors.forename: Ismail
authors.initials: I
authors.lastname: Ozdemir
authors.forename: Elif
authors.initials: E
authors.lastname: Yildiz
authors.forename: Tayfun
authors.initials: T
authors.lastname: Gungor
authors.forename: Selahattin
authors.initials: S
authors.lastname: Kumru
mesh_terms: D000291:Adnexal Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery; D001208:Asia / Q000453:epidemiology; D018394:CA-125 Antigen / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery; D010139:Pacific Islands / Q000453:epidemiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014463:Ultrasonography
chemical_list: D018394:CA-125 Antigen