This cross-sectional analytic study assessed the diagnostic accuracy of IOTA Simple Rules versus serum CA 125 in women with adnexal masses undergoing surgery. Eighty-two percent of tumors were classifiable by IOTA criteria; CA 125 cut-offs of 35, 70, and 105 U/mL were evaluated against histopathology gold standard.

All women admitted to the Department of Obstetrics and Gynecology and assigned for the surgery of adnexal mass were enrolled in the study. After written informed consent, the clinical proforma was filled up. Data collection regarding age, current or previous hormonal contraception, menopausal status and family history of breast or ovarian cancer, clinical presentation. Participants were scheduled for ultrasound evaluation done according to IOTA simple rules (five malignant features and five benign features) and peripheral blood was collected for tumor marker serum CA125 measurement.

During ultrasonographic examination, the morphology of the adnexal masses was characterized using 2D real-time and color Doppler ultrasound. Adnexal masses were described according to origin (ovarian/extra ovarian); position (right/left/bilateral); number of lesions; type of lesions (unilocular/unilocular - solid/multilocular/multilocular - solid); size; volume; intracystic fluid echogenicity; number of locations; presence and size of septations; presence, number, size of solid papillary projections; largest solid component; presence / absent of ascites. These parameters are used as designation according to IOTA Group.

For the sample of CA125, approximately 2 ml blood was collected and registered patient's hospital number, then the selected reagent was added to the sample and kept in a fully automated immunoassay system in the hospital laboratory where electrochemiluminescence Immunoassay method (ECLIA) is used for the analysis. Surgery was performed in the hospital and a biopsy was sent for the histopathology examination in the same hospital.

Sensitivity, specificity, positive predictive value, and negative predictive values of CA125 and IOTA class were calculated. The correlation between CA 125 and IOTA simple rules was analyzed and compared with histopathological reports using the Pearson correlation method. The area under the receiver operating characteristic curve (AUC) was used to determine the point at which CA125 had the highest sensitivity and specificity in distinguishing histologically malignant from benign tumors.

Inclusion Criteria:

• All age groups and parity with ovarian mass admitted for scheduled surgery.

Exclusion Criteria:

• Proven cases of ovarian malignancy
• Ovarian mass in pregnancy

The patient assigned for surgery due to an ovarian tumor in the Department of Obstetrics and Gynecology, Nobel Medical College Teaching Hospital (NOMCTH), Kanchanbari 5, Biratnagar