Ovarian Adnexal Reporting Data System (O-RADS) for Classifying Adnexal Masses: A Systematic Review and Meta-Analysis

Abstract

In this systematic review and meta-analysis, we aimed to assess the pooled diagnostic performance of the so-called Ovarian Adnexal Report Data System (O-RADS) for classifying adnexal masses using transvaginal ultrasound, a classification system that was introduced in 2020. We performed a search for studies reporting the use of the O-RADS system for classifying adnexal masses from January 2020 to April 2022 in several databases (Medline (PubMed), Google Scholar, Scopus, Cochrane, and Web of Science). We selected prospective and retrospective cohort studies using the O-RADS system for classifying adnexal masses with histologic diagnosis or conservative management demonstrating spontaneous resolution or persistence in cases of benign appearing masses after follow-up scan as the reference standard. We excluded studies not related to the topic under review, studies not addressing O-RADS classification, studies addressing MRI O-RADS classification, letters to the editor, commentaries, narrative reviews, consensus documents, and studies where data were not available for constructing a 2 × 2 table. The pooled sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (DOR) were calculated. The quality of the studies was evaluated using QUADAS-2. A total of 502 citations were identified. Ultimately, 11 studies comprising 4634 masses were included. The mean prevalence of ovarian malignancy was 32%. The risk of bias was high in eight studies for the “patient selection” domain. The risk of bias was low for the “index test” and “reference test” domains for all studies. Overall, the pooled estimated sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and DOR of the O-RADS system for classifying adnexal masses were 97% (95% confidence interval (CI) = 94%–98%), 77% (95% CI = 68%–84%), 4.2 (95% CI = 2.9–6.0), 0.04 (95% CI = 0.03–0.07), and 96 (95% CI = 50–185), respectively. Heterogeneity was moderate for sensitivity and high for specificity. In conclusion, the O-RADS system has good sensitivity and moderate specificity for classifying adnexal masses.

Risk stratification and validation of ultrasound ovarian and adnexal reporting data system: Correlation with clinical follow-up and histopathology

“…In contrast, among ORADS Grades 1,2 and 3, no major surgical procedure was carried out. Our observation was similar to observations by Jha et al [13] and Ahmed et al [14] who noted that patients with higher grades of ORADS had underwent invasive surgical procedures.…”

“…The IOTA model was the most studied one till the advent of ORADS system. Basha et al [14] . Determined the malignancy rates, validity and reliability of the O-RADS approach when applied to a database of 647 adnexal masses collected before the development of the O-RADS system.…”

Nomogram based on the O-RADS for predicting the malignancy risk of adnexal masses with complex ultrasound morphology

“…A multicenter study [22] derived from 4905 masses for external validation of the O-RADS conducted that the O-RADS had 0.92 sensitivity and 0.80 specificity at the 10% risk threshold (O-RADS 4). A meta-analysis [15] involving 4634 adnexal masses from 11 studies showed that the sensitivity and specificity of the O-RADS were 0.97 and 0.77, respectively. Even though the overall diagnostic efficacy and sensitivity were good, relatively low specificity was still inevitable; in the study of Hiett et al, which only included 150 patients with adnexal masses and set the malignant risk threshold at 10% directly, the specificity was only 0.466 [23].…”

“…Recently, the American College of Radiology (ACR) released the Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound lexicon [ 14 ] and consensus guideline of risk stratification and management [ 12 ], which provide a standardized ultrasound lexicon for adnexal lesions and associated management schemes for all risk categories. The current studies showed that the O-RADS had a high diagnostic sensitivity but relatively low specificity [ 15 – 17 ], which means that the O-RADS can misdiagnose some benign masses as malignant and lead to overtreatment. Some scholars have proposed that the acoustic shadowing should be included in O-RADS classification system to improve its performance [ 18 ].…”

Differentiating benign from malignant ovarian masses with solid components: diagnostic performance of CEUS combined with IOTA simple rules and O-RADS

“…Although the risk strati cation proposed by IOTA SR and O-RADS has been prospectively and externally validated, their performance was found to vary signi cantly across different reported studies [3,[17][18][19][20][21].…”