The Diagnostic Accuracy of International Ovarian Tumor Analysis Simple Rules (IOTA) to Discriminate Between Benign and Malignant Adnexal Masses

Abstract

Introduction: The most widely validated strategies for discrimination between malignant and benign adnexal masses are the methods established by the International Ovarian Tumor Analysis (IOTA) group. The IOTA group has formulated simple rules for ultrasound that differentiate malignant from benign adnexal masses.

Objective: To determine the diagnostic accuracy of IOTA SR in predicting malignancy among patients presenting with adnexal mass taking histopathology as gold standard.

Study Design: Validation study.

Place and Duration of Study: Department of Obstetrics & Gynaecology, Fauji Foundation Hospital, Rawalpindi from July 19, 2025 to January 18, 2026.

Methodology: All together 225 females 18–60-year-old with adnexal masses diagnosed on transvaginal ultrasonography (availability of cystic, solid, or mixed mass) were recruited from gynaecology ward of Fauji Foundation Hospital, Rawalpindi. Diagnosis of malignant lesions were made based on the IOTA SR as per-operational definitions. Following this biopsy samples from all patients were collected and transferred to central hospital lab for malignancy determination on histopathology reporting. Data were gathered on a proforma and statistical analysis was done using SPSS version 22.

Results: A total of 225 patients (mean age 43.34 ± 10.95 years) were involved, with the majority being 41–60 years old (60.0%). IOTA SR had high accuracy: sensitivity 91.53%, specificity 93.75%, PPV 98.18%, NPV 75.00%, and overall accuracy 92.00% (p < 0.001). Subgroup analysis based on age and menopausal status revealed consistent performance, with only slight differences, affirming its reliability between groups.

Conclusion: In conclusion, IOTA SR had excellent diagnostic accuracy relative to histopathology, with high sensitivity, specificity, and predictive values in all subgroups. Its high PPV and stable performance in premenopausal and postmenopausal women emphasize its reproducibility for malignancy prediction in adnexal masses.

Keywords: Benign adnexal mass; International Ovarian Tumor Analysis (IOTA) simple rules; Malignant adnexal mass