The contribution of ADC and contrast-enhanced imaging to ORADSclassification in adnexal masses

Introduction and Objective: Adnexal masses are common findings in gynecological diseases and are important for diagnostic accuracy and treatment planning. However, distinguishing between benign, intermediate, and malignant types of these masses can be challenging. There are numerous studies in the literature that demonstrate the value of the Ovarian-Adnexal Reporting and Data System (O-RADS) classification in conjunction with dynamic pelvic magnetic resonance imaging (MRI). However, there have been no reported studies on the impact of non-dynamic conventional pelvic MRI on the O-RADS classification. The aim of this study is to investigate the contribution of Diffusion-Weighted Imaging (DWI) and contrast-enhanced imaging in the evaluation of adnexal masses to the O-RADS classification. Methods: Our study included 96 patients who underwent preoperative contrast-enhanced MRI and had pathological results at Turgut Özal Medical Center between 2012 and 2023. The data were retrospectively analyzed and analyzed using the statistical program SPSS v26. In cases with ovarian masses, ADC values were obtained for lesions from three separate points on the histogram circle by two radiologists. Risk scores were created using time-intensity curves in dynamic imaging and measurements from the outer half of the lesion to the myometrium in non-dynamic imaging. The contribution of ADC and dynamic curve scores to the O-RADS classification was studied based on the data. Findings: According to the O-RADS scoring, malign lesions tend to be more solid in 73.9% and 72.7% of cases, respectively, compared to other lesions, while benign and intermediate lesions tend to be more cystic (p=<0.006). There was a statistically significant relationship among readers for O-RADS scores, ADC measurements, dynamic curve measurement scores, and risk scores generated from non-dynamic measurements (p=<0.0001). No statistically significant relationship was found among readers for ADC measurements and dynamic-non-dynamic curve risk scores (p>0.05). When evaluated in terms of dynamic curve measurement scores, a significant (advanced level) statistically significant diagnostic agreement was found between the two readers (ƙ=0.797, p=<0.0001). When evaluated in terms of O-RADS scores, a significant (good level) statistically significant diagnostic agreement was found between the two readers ix (ƙ=0.653, p=<0.0001). When evaluated in terms of ADC measurements, a very high (very good level) statistically significant diagnostic agreement was found between the two readers (ƙ=0.653, p=<0.0001). Conclusion: We believe that ADC values and contrast-enhanced MRI demonstrate significant prognostic potential in the O-RADS MRI classification system, which contributes to better radiological standardization and characterization of adnexal masses. Therefore, the O-RADS classification improves the clinical approach and management of patients with ovarian tumors. It is valuable in avoiding unnecessary surgery for benign lesions and improving the pharmacological and surgical management of malignant lesions. Our results demonstrated that both dynamic and conventional contrast-enhanced pelvic MRI, within the O-RADS classification, provide valuable information. Additionally, we showed that ADC measurements are a valuable tool. Based on our study, we can say that inexperienced readers can reach accurate results comfortably using the O-RADS classification, similar to experienced users. Our findings provide a potential roadmap for future research. Particularly, prospective studies conducted on a larger patient population can further enhance the effectiveness of ADC and contrast-enhanced imaging in clinical practice.Keywords: ADC, Adnexal Mass, Contrast-enhanced MRI, ORADS