MRI Characterization Of The Endometrial Cavity Masses

Purpose To evaluate the diagnostic values of magnetic resonance imaging(MRI)in distinguishing endometrial polyps,submucosal leiomyoma and endometrial carcinoma.Materials and Methods Retrospective analysis the cases with hysterectomy or hysteroscopy operation and confirmed by pathology from November 2014 to July 2019 in Tianjin Medical University General Hospital,including 65 endometrial polyps,80 submucosal leiomyomas and 117 endometrial carcinomas,all of the cases underwent preoperative3.0T pelvic MRI examinations within 3 weeks before the operation.The patient were divided into three groups,the endometrial polyps,submucosal leiomyoma and endometrial carcinoma.Two radiologists independently assessed the MRI features including direct signs and indirect signs,direct signs include the largest diameter of the lesion;aspect ratio of lesion;signal intensity on T2 WI and DWI;the ADC values,the fibrous core;intratumoral cysts;necrosis and boundary of the lesion;indirect signs include endometrial cavity thickness;endometrial cavity hemorrhage;muscle invasion;flow void;pedicle;filling the cavity;endometrium visibility;boundary between lesion and endometrium.For the continuous variables of the three groups,comparisons were performed by Oneway ANOVA(analysis of variance)and inter-group comparisons were corrected by Bonferroni,and for categorical variables,comparisons were performed by Pearson’s chi-squared test or Fisher’s exact test and inter-group comparisons were performed by partitions of χ2 method.The positive predictive value(PPV),negative predictive value(NPV),sensitivity and specificity were measured for the significant signs.Receiver operating characteristic(ROC)curve was used and the cut-off value was obtained to evaluate the diagnostic efficacy.Results The MRI features show significant difference among endometrial polyps,submucosal leiomyoma and endometrial carcinoma.For the differential diagnosis between endometrial polyps and endometrial carcinoma,the ADC values and DWI signal intensity show higher diagnostic values with the AUC >0.9;muscle invasion,fibrous core,intratumoral cysts and necrosis show moderate diagnostic values with the AUC values between 0.7 and 0.9.While for the differential diagnosis between endometrial polyp and submucosal leiomyoma,the aspect ratio,ADC values,fibrous core,intratumoral cysts,boundary of the lesion,boundary between lesion and endometrium,T2 WI signal intensity show moderate diagnostic values with the AUC values between 0.7 and 0.9.For the differential diagnosis between submucosal leiomyoma and endometrial carcinoma,the aspect ratio,ADC values,boundary of the lesion,boundary between lesion and endometrium,DWI intensity show higher diagnostic values with AUC>0.9;endometrium visibility and T2 WI signal intensity show moderate diagnostic values with the AUC values between 0.7 and 0.9.Conclusion The characteristics of MRI images show moderate or higher diagnostic value for the differentiation among EC,EP and SL.