3．0T磁共振DWI结合T2WI鉴别前列腺移行区的良恶性结节  

Benign and malignant nodule in prostatic transition zone： differential diagnosis by MR T2 weighted image in combination with DWI at 3.0T

作　　者：任静[1] 刘燕丽[1] 常英娟[1] 葛雅丽[1] 张贝[1] 宦怡[1] 

机构地区：[1]第四军医大学西京医院放射科,陕西西安710032

出　　处：《实用放射学杂志》2011年第8期1208-1212,共5页Journal of Practical Radiology

摘　　要：目的探讨分别应用T2WI、DWI以及综合应用2种成像序列对前列腺移行区良恶性结节的鉴别诊断价值。方法收集2006-08—2010—04在本院3．0T磁共振行常规及DWI扫描（b值分别为0s／mm2和800s／mm2）的前列腺疾病患者，其中70例前列腺移行区见到结节样异常信号者被纳入本研究，本组患者后来均行超声引导下经直肠前列腺穿刺活检术。分析良恶性结节的MRI表现，比较其ADC值。采用5分制评分，将所得结果与病理结果对照，用SPSS11．5分别做受试者工作特征曲线（ROC），分析比较各组方法诊断的敏感度和特异度。结果病理证实54例患者为前列腺移行区良性结节，16例为移行区前列腺癌（prostate cancer，Pea），良性和恶性结节的ADC值分别为（1．352±0．0885）×10^-3mm^2／s和（0．931±0．0795）×10^-3mm^2／s，恶性结节的ADC值明显低于良性结节（P〈O．05）。联合DWI和T2WI2种成像序列鉴别前列腺移行区良恶性结节的ROC曲线下面积（AUC）最大（0．993，95％CI：0．935～O．995），其与单独应用TzwI的AUC之间的差异有统计学意义（Z=2．093，P〈O．05），但是与单独应用DWI的AUC之间的差异无统计学意义（Z=O．905，P=0．365）；T2WI鉴别前列腺移行区良恶性结节的AUC低于DWI的，但两者之间的差异无统计学意义（Z=1．629，P=0．103），2种序列结合鉴别前列腺移行区良恶性结节的特异度和敏感度最高。结论前列腺移行区恶性结节的ADC值明显低于良性结节；联合应用DWI和T2WI鉴别诊断良恶性结节的特异度和敏感度最高。Objective To study the value of MR diffusion weighted imaging （DWI） and apparent diffusion coefficient （ADC） values in distinguishing the malignant nodule from benign nodule in prostate transition zone. Methods 70 patients with prostate transition zone nodules underwent conventional MRI and DWI （b value： 0, 800 s/mm2 ） examinations during 2006--08--2010--04 in our hospital. All the 70 cases were underwent per-rectum needle biopsy examination. DWI appearances of all benign and malignant nodules in prostate transition zone were analyzed, and the ADC values were measured. T2 weighted images alone and then T2 weighted images combined with DWI were scored for the likelihood of malignant nodule on the basis of radiologists＇ written reports. The area under the receiver operating characteristic curve {AUC） was used to assess the accuracy. The sensitivity, specificity, positive predictive value, and negative predictive value for predicting malignant nodule in prostate transition zone were calculated. Statistical significance was inferred at P〈0.05. Results After needle biopsy examination, 54 （77.1%） of 70 cases were pathologically proven benign nodules, and 16 （22.9% ） cases were malignant nodules. The mean ADCs of benign and malignant nodules in prostate transition zone were （1. 352±0. 088 5）×10^-3 mm^2/s and （0. 931±0. 079 5） ×10^-3 mm^2/s,respectively. The ADC values of malignant nodules were significantly lower than those of benign ones （P= 0. 000 ）. The AUC for T2 weighted image plus DW imaging （0. 993, 95% CI：0. 935-0. 995） was significantly larger than that for T2 weighted image alone （0. 896,95%CI：0. 800-0. 956,P〈0.05）. Conclusion ADC values of malignant nodules in prostatic transition zone were lower compared with benign ones. T2 weighted image in combination with DWI is significantly better than T2 weighted image alone in the detection of malignant nodules in prostate transition zone.

关 键 词：前列腺 前列腺癌 磁共振成像 

分 类 号：R737.25[医药卫生—肿瘤] R445.2[医药卫生—临床医学]