O-RADS Classification for Ultrasound Assessment of Adnexal Masses: Agreement between IOTA Lexicon and ADNEX Model for Assigning Risk Group

Abstract

Background: The O-RADS system is a new proposal for establishing the risk of malignancy of adnexal masses using ultrasound. The objective of this study is to assess the agreement and diagnostic performance of O-RADS when using the IOTA lexicon or ADNEX model for assigning the O-RADS risk group. Methods: Retrospective analysis of prospectively collected data. All women diagnosed as having an adnexal mass underwent transvaginal/transabdominal ultrasound. Adnexal masses were classified according to the O-RADS classification, using the criterion of the IOTA lexicon and according to the risk of malignancy determined by the ADNEX model. The agreement between both methods for assigning the O-RADS group was estimated using weighted Kappa and the percentage of agreement. The sensitivity and specificity of both approaches were calculated. Results: 454 adnexal masses in 412 women were evaluated during the study period. There were 64 malignant masses. The agreement between the two approaches was moderate (Kappa: 0.47), and the percentage of agreement was 46%. Most disagreements occurred for the groups O-RADS 2 and 3 and for groups O-RADS 3 and 4. The sensitivity and specificity for O-RADS using the IOTA lexicon and O-RADS using the ADNEX model were 92.2% and 86.1%, and 85.9% and 87.4%, respectively. Conclusion: The diagnostic performance of O-RADS classification using the IOTA lexicon as opposed to the IOTA ADNEX model is similar. However, O-RADS group assignment varies significantly, depending on the use of the IOTA lexicon or the risk estimation using the ADNEX model. This fact might be clinically relevant and deserves further research.

A Comprehensive Review of Screening Methods for Ovarian Masses: Towards Earlier Detection

“…At its core, O-RADS categorizes ovarian masses into distinct risk groups, such as O-RADS 1 for benign lesions and O-RADS 5 for malignant or highly suspicious lesions. These categories are determined based on the presence or absence of various ultrasound features, including the size, shape, internal structure, vascularity, and other specific mass characteristics [ 49 ].…”

Effect of differences in O-RADS lexicon interpretation between senior and junior sonologists on O-RADS classification and diagnostic performance

“…Ultrasound is the first-line imaging technique for the evaluation of adnexal masses (Vara et al 2023 ). However, there is a lack of standardized terminology for gynecologic imaging, which may lead to variation in the interpretation of results between local institutions, and consequently, patients may miss out on the best clinical management strategies (Andreotti et al 2018 ).…”

“…However, there is a lack of standardized terminology for gynecologic imaging, which may lead to variation in the interpretation of results between local institutions, and consequently, patients may miss out on the best clinical management strategies (Andreotti et al 2018 ). Due to the highly subjective nature of ultrasonography, the subjective assessment of an experienced sonologist is still the most accurate method of gynecologic ultrasonography (Vara et al 2023 ; Vázquez-Manjarrez et al 2020 ). To improve the consistency and accuracy of ultrasound, the American College of Radiology (ACR) promulgated the Ovarian-Adnexal Reporting and Data System (O-RADS) lexicon in 2018 and built on it with the O-RADS ultrasound risk stratification and management system in 2020 (Andreotti et al 2018 , 2020 ).…”