Department of Radiology, Kurashiki Central Hospital, Kurashiki, Japan.
J Magn Reson Imaging. 2012 Jun;35(6):1414-21. doi: 10.1002/jmri.23587. Epub 2012 Jan 13.
To investigate the usefulness of targeted biopsy strategy based on apparent diffusion coefficient (ADC) maps in the detection and localization of prostate cancer.
Institutional review board approval and informed consent from all participants were obtained. This study included 1448 consecutive patients suspected of having prostate cancer based on PSA level, who were divided into two groups: Group A included 890 patients with low-ADC lesions who underwent targeted and systematic biopsies; Group B included 558 patients with no low-ADC lesions who underwent only systematic biopsies. The cancer detection rates (CDR) of each group, positive predictive value (PPV), and negative predictive value (NPV) of ADC maps were calculated.
The CDR was 70.1% for Group A, higher than those for overall patients (48.1%) and for Group B (13.1%) with significant difference (P < 0.001). In the serum, PSA range from 4 to 20 ng/mL, the CDR was higher for the Group A than for the Group B and overall patients with significant differences. PPV and NPV of MR findings were 70.1% and 86.9%, respectively. Especially, the PPV of the MR findings for the anterior portion was as high as 90.1%. Among the false negatives of MR findings, Gleason score proved 6 or smaller in 79.5%, and positive core number was merely one or two in 80.8%.
The targeted biopsy strategy based on ADC maps can be useful in the detection and localization of prostate cancer with high PPV.
探讨基于表观扩散系数（ADC）图的靶向活检策略在前列腺癌检测和定位中的作用。
本研究获得了机构审查委员会的批准和所有参与者的知情同意。这项研究纳入了 1448 例基于 PSA 水平怀疑患有前列腺癌的连续患者，将其分为两组：A 组包括 890 例 ADC 值低的患者，行靶向和系统活检；B 组包括 558 例无低 ADC 值的患者，仅行系统活检。计算每组的癌症检出率（CDR）、阳性预测值（PPV）和阴性预测值（NPV）。
A 组的 CDR 为 70.1%，高于总体患者（48.1%）和 B 组（13.1%），差异有统计学意义（P<0.001）。在血清 PSA 为 4~20ng/ml 范围内，A 组的 CDR 高于 B 组和总体患者，差异有统计学意义。MR 检查的 PPV 和 NPV 分别为 70.1%和 86.9%。特别是，MR 检查对前区的 PPV 高达 90.1%。MR 检查结果的假阴性中，Gleason 评分 6 或更低的占 79.5%，阳性核心数仅为 1 或 2 的占 80.8%。
基于 ADC 图的靶向活检策略在提高 PPV 的情况下，对前列腺癌的检测和定位具有重要作用。
