Diagnostic role of ovarian – adnexal reporting and data system magnetic resonance imaging scoring system for evaluation of indeterminate adnexal lesions

Abstract

Introduction: Magnetic resonance imaging (MRI) plays an important role in distinguishing malignant from benign adnexal mass which are  indistinguishable from ultrasonography.This can help in early diagnosis and treatment of indeterminate adnexal lesions.This study aims to evaluate the accuracy of ovarian adnexal reporting and data system (O-RADS) MRI score in distinguishing  bening from malignant lesion when compared to histopathology which is the gold standard  and  evaluate MRI features  suggesting malignancy  in such lesions.

Method: This was a retrospective study of MRI pelvis carried out in patients with indeterminate adnexal lesions who had MRI pelvis done from 2018 to 2022 at Patan Hospital, Lalitpur, Nepal. Ethical approval was obtained from the institutional review committee of Patan Academy of Health Sciences. MRI diagnosis based on O-RADS MRI score was compared with histopathology diagnosis and sensitivity, specificity were calculated. Chi-square test was used and p-value less than 0.05 was considered statistically significant.

Result: Among 175 patients, 135 had benign and 40 had malignant lesions. The sensitivity and specificity of MRI diagnosing indeterminate lesion was 92.5% and 91.85% respectively. Among malignancy, 92.5% had O-RADS MRI score of 4 and 5. Significant statistical association of O-RADS MRI score was found with histopathology diagnosed malignancy. MRI features of malignancy were multilocular, solid cystic lesion with contrast enhancement, septations and diffusion restriction. Malignancy was common in middle aged patients (41-60 y).

Conclusion: O-RADS MRI scoring is significantly associated with histopathology-proven adnexal malignancy and hence helps in accurately diagnosing indeterminate adnexal lesions and stratifying the risk of malignancy.