Introduction/Background Various modalities including ultrasonography and magnetic resonance imaging (MRI) have been developed as imaging technique for screening malignant myometrial tumors, but a few studies assessed the diagnostic value of these two techniques in differentiation of benign from malignant myometrial tumors that had been the main purpose of this study.

Methodology This cross-sectional study was performed on 63 women underwent surgery for intrauterine masses that were initially assessed using MRI and ultrasound before surgery at a tertiary hospital in Tehran from 2016 to 2020. Their MRI was reviewed by a reputable radiologist in the field. The findings of histopathological assessment were considered as the gold diagnostic standard.

Results The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI to detect sarcoma were revealed to be 94.6%, 92.3%, 94.6%, 92.3%, and 93.7% respectively. Ultrasonography had not preferable applicability to differentiate sarcoma from benign tumors with sensitivity, specificity, PPV, NPV and accuracy of 35.1%, 88.4%, 81.2%, 48.9%, and 57.1% respectively. The diagnostic performance of both modalities was not affected by baseline clinical conditions including pain, abnormal uterine bleeding and menopausal status.

Conclusion MRI but not ultrasonography can effectively differentiate benign from malignant myometrial tumors.