VP63.18: Magnetic resonance imaging versus transvaginal ultrasound with or without 3D and HDlive modalities for assessing myometrial and cervical invasion in endometrial cancer

To evaluate the accuracy of transvaginal ultrasonography (TVS) with or without three dimensional (3D) and high definition real time (HDLive) modalities in comparison to magnetic resonance imaging (MRI) in assessing deep myometrial and cervical involvement in endometrial cancer (EC). This single-centre prospective study included women with histological diagnosis of EC, who underwent TVS and MRI within 4 weeks prior to treatment. One operator performed a conventional TVS; another, blinded to the previous ultrasonographic exam, performed a TVS with the addition of 3D and HDLive modalities. Myometrial involvement (classified ≥ or < than 50%) and cervical involvement were assessed during each exam. Imaging findings were compared with histopathological results. Overall, 164 women with a mean age at diagnosis of 68 ± 7.8 years were included; 78.0% of them had endometrioid, 12.2% serous, 5.5% clear cell and 4.3% mucinous EC histotype; 34.1% of patients had FIGO stage IA, 17.1% stage IB, 18.9% stage II and 29.9% stage III EC. There was no significant difference in the accuracy of TVS and MRI in predicting myometrial invasion (p = 0.098); the addition of 3D and HDlive modalities did not increase the accuracy of TVS in predicting myometrial invasion. At logistic univariate analysis, the presence of uterine fibroids, diffuse adenomyosis and BMI more than 30 kg/m2 were associated with a lower accuracy of TVS in diagnosing myometrial invasion. There was no significant difference in the accuracy of MRI, TVS with and withouth 3D and HDLive modalities in diagnosing cervical involvement (p = 0.242). TVS and MRI have a similar diagnostic accuracy in predicting myometrial and cervical invasion in patients with EC. 3D and HDlive modalities do not increase the accuracy of TVS in predicting myometrial and cervical invasion. MRI may be employed in case of obesity, uterine fibroids and adenomyosis as low quality ultrasonographic scans tend to be obtained in these patients.