标准化ADC值鉴别移行带前列腺癌与间质为主增生结节

Differentiation of Transition Zone Prostate Cancer and Stromal Hyperplasia Using Normalized ADC

【目的】采用磁共振弥散加权成像比较绝对表观弥散系数(ADC)值及标准化ADC值在鉴别移行带前列腺癌及间质为主增生结节的效能。【方法】55例临床怀疑前列腺癌的男性患者行MRI平扫及弥散加权成像检查,使用b值为0、1 000s/mm2。所有患者在MR检查后1个月内行经直肠超声引导下前列腺穿刺活检。分别比较外周带前列腺癌及移行带前列腺癌的ADC值及标准化ADC值,移行带前列腺癌与间质为主增生结节的ADC值及标准化ADC值。使用受试者工作特征曲线评估标准化ADC值与ADC值在鉴别移行带前列腺癌与增生结节的效能。【结果】共36例经病理证实前列腺癌的患者纳入分析。包括移行带癌灶26个,外周带癌灶37个,移行带癌与外周带癌的ADC值及标准化ADC值差异无统计学意义P分别为0.204、0.308。移行带癌灶的ADC值及标准化ADC值均明显低于移行带间质增生结节(P<0.05)。标示准化ADC值和绝对ADC值鉴别移行带前列腺癌和间质增生结节的ROC曲线下面积无统计学差异,分别为1.000、0.997(P=0.4111);但当特异性设定为100%时,标准化ADC值较绝对ADC值具有更高的敏感性,分别为100%和92.3%。【结论】标准化ADC值鉴别移行带前列腺癌与间质为主增生结节的效能与绝对ADC值相当,在保持高特异性的同时标准化ADC值较绝对ADC值具有更高的诊断敏感性。

[Objective] The purpose of this study was to compare the diagnostic performance of apparent diffusion coefficient （ADC） versus normalized ADC using the peripheral zone （PZ） as a reference site for the differentiation of transition zone （TZ） prostate cancer （Pca） and stromal hyperplasia （SH）. [Methods] A total of 55 consecutive male patients with suspected prostate cancer were referred for MR plain scan and diffusion-weighted imaging using b values of 0 and 1000 s/mm2. All patients underwent transrectal ultrasound （TRUS）-gnided biopsy of the prostate within one month after MR imaging. The differences between normalized ADC and ADC of PZ and TZ prostate cancer, between normalized ADC and ADC of TZ prostate cancer and stromal hyperplasia （SH） were compared, respectively. Receiver operating characteristic （ROC） analysis was used to determine the performance of ADC and normalized ADC for prediction of TZ prostate cancer and SH. [Results] Thirty-six Pca patients was included in our study, including 37 PZ Pca foci and 26 TZ Pca foci. The ADC and normalized ADC had no statistic significance between PZ Pca and TZ Pca （P = 0.204, 0.308, respectively）. The ADC and normalized ADC of 26 TZ Pca was significantly lower than corresponding 24 SH （P〈 0.05）. Area under the ROC curve of normalized ADC and ADC was without a difference for the differentiation of TZ prostate cancer and SH （1.000 vs 0.997; P=0.4111 ）. However, when set the specificity to 100%, normalized ADC had higher sensitivity than ADC （100% vs 92.3% ）. [Conclusion] Normalized ADC had similar performance to ADC for the differentiation of TZ prostate cancer and SH, with higher sensitivity while kept high specificity.