Kato Seiji, Kamijima Shuichi, Inaoka Tsutomu, Kamiya Naoto, Sasai Daisuke, Terada Hitoshi, Hiruta Nobuyuki, Suzuki Hiroyoshi
a Department of Urology , Toho University Sakura Medical Center , Sakura , Japan.
b Department of Radiology , Toho University Sakura Medical Center , Sakura , Japan.
Scand J Urol. 2018 Jun;52(3):180-185. doi: 10.1080/21681805.2018.1481143. Epub 2018 Jun 25.
Apparent diffusion coefficient (ADC) values on multiparametric magnetic resonance imaging (mpMRI) have been reported to correlate with high-Gleason score (GS) prostate cancer. However, the relative ADC values between tumor lesions and normal tissue have been suggested as more suitable than the absolute ADC values for evaluation of diffusion abnormalities, because absolute ADC values are susceptible to differences in scanners or scanner settings. The present study evaluated the usefulness of the relative assessment of ADC values between tumor lesions and normal tissue on preoperative mpMRI for the prediction of high-risk prostate cancer on radical prostatectomy specimens.
A retrospective analysis of 48 men who underwent radical prostatectomy between January 2013 and December 2014 was conducted. MpMRI was performed with a 3.0-T scanner using b-values of 0 and 1500 s/mm. ADC values of the tumor (ADC) and normal prostate and the relative ADC tumor/normal ratio (ADC) were evaluated by two radiologists.
The inter-rater reliability between two radiologists for ADC measurement was high, with Pearson's r = 0.982. There was no difference in ADC between GS ≤7 and GS ≥8. In contrast, ADC was significantly lower in GS ≥8 than in GS ≤7. ROC curves of ADC to predict higher GS (≥8) showed better classification performance (AUC = 0.8243, p = .0012 by radiologist A and AUC = 0.7961, p = .0031 by radiologist B) than of ADC.
The relative assessment of ADC values between tumor lesions and normal tissue could improve the detection rate of high-risk prostate cancers.
多参数磁共振成像（mpMRI）上的表观扩散系数（ADC）值已被报道与高格里森评分（GS）前列腺癌相关。然而，肿瘤病变与正常组织之间的相对ADC值被认为比绝对ADC值更适合评估扩散异常，因为绝对ADC值易受扫描仪或扫描仪设置差异的影响。本研究评估了术前mpMRI上肿瘤病变与正常组织之间ADC值的相对评估对预测根治性前列腺切除标本中高危前列腺癌的有用性。
对2013年1月至2014年12月期间接受根治性前列腺切除术的48名男性进行回顾性分析。使用3.0-T扫描仪进行mpMRI检查，b值为0和1500 s/mm²。两名放射科医生评估肿瘤的ADC值（ADCₜ）、正常前列腺的ADC值以及相对ADC肿瘤/正常比值（ADCₜ/ₙ）。
两名放射科医生对ADC测量的评分者间可靠性较高，皮尔逊相关系数r = 0.982。GS≤7和GS≥8之间的ADCₜ无差异。相比之下，GS≥8时的ADCₜ/ₙ显著低于GS≤7时。预测更高GS（≥8）的ADCₜ/ₙ的ROC曲线显示出比ADCₜ更好的分类性能（放射科医生A的AUC = 0.8243，p = 0.0012；放射科医生B的AUC = 0.7961，p = 0.0031）。
肿瘤病变与正常组织之间ADC值的相对评估可提高高危前列腺癌的检出率。
