Comparative Diagnostic Accuracy of Risk of Malignancy Index Versus International Ovarian Tumor Analysis Model in Predicting Malignancy in Adnexal Masses: An Analytical Comparative Cross-Sectional Study: Malignancy Index Versus IOTA Model in Predicting Malignancy in Adnexal Masses

Mishal Maqbool; Naushin Farooq; Zahra Kausar; Laila Khalid; Sabeen Aslam; . Fariha

doi:10.54393/pjhs.v7i10.3854

Authors

Mishal Maqbool Department of Obstetrics and Gynecology, Cavan General Hospital, Cavan, Ireland
Naushin Farooq Department of Obstetrics and Gynecology, Federal Government Polyclinic Hospital, Islamabad, Pakistan
Zahra Kausar Department of Obstetrics and Gynecology, Federal Government Polyclinic Hospital, Islamabad, Pakistan
Laila Khalid Department of Obstetrics and Gynecology, Federal Government Polyclinic Hospital, Islamabad, Pakistan
Sabeen Aslam Department of Obstetrics and Gynecology, Federal Government Polyclinic Hospital, Islamabad, Pakistan
. Fariha Department of Obstetrics and Gynecology, Pakistan Institute of Medical Sciences, Islamabad, Pakistan

DOI:

https://doi.org/10.54393/pjhs.v7i10.3854

Keywords:

Adnexal Lesions, Risk of Malignancy Index, Ultrasound, Adnexal Masses, International Ovarian Tumor Analysis

Abstract

Correct pre-surgical discrimination between benign and malignant adnexal lesions is critical for appropriate operative decision-making. Risk of Malignancy Index (RMI) and international ovarian tumor analysis (IOTA) models combine clinical and ultrasound findings to assess ovarian tumor malignancy risk. However, evidence comparing their diagnostic accuracy remains limited. Objectives: To determine the comparative diagnostic performance of standalone RMI versus an integrated RMI–IOTA approach for preoperative detection of malignancy in adnexal lesions. Methods: This analytical comparative cross-sectional study was conducted at the Pakistan Institute of Medical Sciences from 1 February 2023 to 30 August 2023. A total of 49 women with adnexal masses ≥5 cm scheduled for surgical intervention were enrolled using non-probability consecutive sampling. The women with measurable serum, complete ultrasonographic, and IOTA evaluation were included. Pregnant women, conservatively managed cases were excluded. All participants underwent transabdominal and/or transvaginal ultrasonography, serum CA-125 testing, and risk stratification using RMI and IOTA Analysis models. Histopathology served as the reference standard. Results: Only 1 (2.0%) had a borderline tumor, 13 (26.5%) malignant, and 35 (71.4%) benign. The RMI identified 10/13 malignant cases (sensitivity 76.9%) and 31/35 benign cases (specificity 88.5%). The ultrasound score showed sensitivity of 76.9% (10/13) and specificity of 74.2% (26/35). The IOTA classified 5/49 (10.2%) as malignant, 25/49 (51.0%) as benign, and 19/49 (38.7%) as inconclusive. Conclusions: RMI demonstrated more reliable diagnostic performance than the IOTA model for preoperative assessment of adnexal masses. So, the RMI can be continually used as an effective tool for guiding clinical decision-making and surgical planning.

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