3.0T MR动态增强成像对宫腔良恶性占位病变的鉴别诊断价值

Value of 3.0T MR Dynamic Contrast-enhanced Imaging in Differentiating Malignant from Benign Mass in Uterine Cavity

目的:探讨动态增强MR(DCE-MRI)对宫腔良恶性占位病变的鉴别诊断价值。方法:经病理证实的子宫内膜癌32例、宫腔良性占位病变30例行常规MRI和DCE-MRI检查。使用卡方检验比较良恶性病变的形态学特征、TIC曲线差别。使用独立样本t检验比较DCE-MRI半定量参数:包括强化峰值(SImax)、达峰时间(TTP)、最大相对强化度(SIpeak%)及流出分数(washout),对各参数进行ROC曲线分析以寻求最佳参数及最佳诊断阈值。结果:子宫内膜癌与良性病变的形态学特征(结合带除外)没有统计学差异。子宫内膜癌与良性病变的TIC曲线有统计学差异。良性病变多出现I型曲线,子宫内膜癌多出现Ⅲ型曲线。子宫内膜良恶性病变间各DCE-MRI参数差异均存在统计学意义。ROC曲线分析结果显示TTP与流出分数具有较好的诊断效能。TTP的曲线下面积AUC=0.827,当阈值设为154时,敏感度为81.3%,特异性为76.7%;流出分数的曲线下面积AUC=0.808,当阈值设为0.0853时,敏感度为75.0%,特异性为80.0%。结论:3.0T MR动态增强成像有助于鉴别子宫内膜癌与其他宫腔良性占位病变;在动态增强MR四个参数中TTP和流出分数具有较好的诊断效能。

Purpose： To evaluate the diagnostic value of dynamic contrast-enhanced MRI （DCE-MRI） in differentiating endometrial carcinomas from benign uterine cavity lesions. Methods： Thirty-two cases of endometrial carcinomas and 30 cases of benign lesions, which were proved with histopathological results, were enrolled. All the patients underwent conventional MRI and DCE-MRI. MRI morphological features and TIC between cancers and benign lesions were obtained and compared. Several semi-quantitative parameters of DCE-MRI, including SImax, TTP, SIpeak % and washout were calculated and compared with independent sampled t-test. ROC analysis was used to estimate the best DCE parameters and proper threshold to differentiate cancers and benign lesions. Results： There was no statistical significant difference between endometrial carcinoma and benign lesions in morphological features except junctional zone. TIC was with statistical significance in differentiating benign from malignant lesions. The TIC of endometrial cancer was mainly type III, while benign lesions appeared Type I. All DCE parameters between endometrial carcinoma and benign lesions were with statistical significant differences （P〈0.05）. ROC analysis revealed a discriminatory performance in differentiating cancer and benign lesions of AUC=0.827 for TTP （with threshold of 154, the diagnostic sensitivity was 81.3%, and specificity was 76.7%） and AUC=0.808 for washout （with threshold of 0.0853, the diagnostic sensitivity was 75.0%, and specificity was 80%）. Conelnsion： DCE-MRI is useful for differentiating malignant from benign uterine endometrial cavity lesions, TTP and washout are more effective among 4 parameters of DCE-MRI.