前列腺外周带癌扩散加权成像诊断标准  

Diagnostic criterion of diffusion-weighted imaging for prostatic peripheral zone cancer

作　　者：郭雪梅[1] 王霄英[1] 吴冰[1] 蒋学祥[1] 

机构地区：[1]北京大学第一医院医学影像科,北京大学前沿交叉学科研究院功能成像研究中心,北京100034

出　　处：《中国医学影像技术》2009年第7期1235-1238,共4页Chinese Journal of Medical Imaging Technology

基　　金：2007年度高等学校博士学科点专项科研基金新教师项目(20070001748)

摘　　要：目的探讨磁共振扩散加权成像(DWI)所得的表观扩散系数(ADC)值对前列腺外周带癌的量化诊断效能及诊断标准。方法对40例穿刺活检病理证实的前列腺疾病患者,非癌20例,外周带癌20例,以六分区法为基础,根据穿刺活检结果,将每一扫描层面内两侧外周带归为非癌区或癌区,获得外周带各分区内的最小ADC值。判断诊断效能采用ROC分析。结果癌区ADC值平均(0.98±0.30)×10-3mm2/s,非癌区ADC值平均(1.59±0.29)×10-3mm2/s。根据ROC分析,ADC值诊断前列腺外周带癌的最佳临界值为≤1.24×10-3mm2/s时,敏感性、特异性、准确性分别为80.58%、92.42%、86.73%;只考虑获得较大特异性可选择临界值≤1.04×10-3mm2/s,敏感性、特异性、准确性分别为66.56%、96.95%和86.26%,只考虑获得较大敏感性可选择临界值<1.69×10-3mm2/s,敏感性、特异性、准确性分别为98.63%、37.07%和58.82%。结论可选择分区内最小ADC值≤1.24×10-3mm2/s作为前列腺外周带癌诊断标准。当分区内最小ADC值介于(1.04～1.24)×10-3mm2/s之间时,有可能发生漏诊。Objective To evaluate and testify the diagnostic efficacy of the ADC value of the diffusion-weighted imaging （DWI） in prostatic peripheral zone cancer. Methods There were 40 patients with prostatic diseases proved by ultrasound guided systemic biopsy. DWI scans were performed with 1.5T MR scanner using TOSORPA coil and b value of 800 s/mm^2. The peripheral zones of prostate were divided in six areas and were attributed to noncancerous and cancerous areas according to the results of biopsy. The minimal ADC values of each peripheral zone were recorded and analyzed. Results There were 240 areas, in which 89 areas were cancerous and the others were noncancerous. The mean ADC value of cancerous areas was （0.98±0.30）×10^-3 mm^2/s, while the noncancerous areas was （1.59±0.29） ×10^-3 mm^2/s. The diagnostic sensitivity, specificity and accuracy were 80. 58%, 92.42% and 86.73% respectively with cutoff point ≤1.24×10^-3 mm^2/s, whereas 66.56%, 96.95% and 86.26% respectively with cutoff point ≤ 1.04 ×10^-3 mm^2/s. The diagnostic sensitivity was 98.63%, the specificity was 37.07%, the accuracy was 58.82% with cutoff point （1.69×10^-3 mm^2/s. Conclusion The ADC value ≤1.24×10^-3 mm^2/s should be regarded as the diagnostic standard of prostate cancer. When ADC value is between（1.04 1.24）×10^-3 mm^2/s, some cancer might be missed.

关 键 词：前列腺肿瘤 磁共振成像 扩散加权成像 表观扩散系数 

分 类 号：R737.25[医药卫生—肿瘤] R814.42[医药卫生—临床医学]