Department of Urology/Surgery, University of Cincinnati, Cincinnati, Ohio 45267, USA.
J Endourol. 2013 Jul;27(7):820-5. doi: 10.1089/end.2012.0215. Epub 2013 Jun 6.
The feasibility and diagnostic performance of multiparametric magnetic resonance imaging (mp-MRI) has to be proven further. In this study, we evaluate the role of mp-MRI for targeted biopsy of early stage prostate cancer (PCa).
A total 32 consecutive patients with transrectal ultrasonography (TRUS)-guided biopsy-proven PCa meeting low-risk criteria and pursuing active surveillance were selected to undergo mp-MRI 3 Tesla (3T) with endorectal coil. Patients were divided then into three groups based on the method used to target the mp-MRI designated region of interest (ROI): Group 1 underwent TRUS-guided prostate biopsy using an MRI-based coordinate plan (cognitive targeting). Group 2 underwent MRI-targeted TRUS-guided prostate biopsy using MyLabTMTwice, which superimposed the archived MRI images onto the real-time ultrasonography image allowing targeted biopsy of the ROI (fusion targeting). Group 3 included selected patients who had an elevation in prostate-specific antigen levels, or patients followed after radiation therapy (two patients) for suspicious unifocal MRI lesion recurrence. These patients underwent MRI-guided biopsy of the suspicious ROI using the navigation system DynaTRIM.
The cancer detection rate in group 1 was 33.3% (3 of 10 patients), while in group 2, it was significantly higher at 46.2%. The sensitivity and specificity for group 1 was 45.5% and 33.3%, vs 61.9% and 20.8% in group 2, respectively. The positive predictive value in group 1 was 50.0% vs 53.8% in group 2 (P=0.04). In group 3, the cancer detection rate was much higher (80%) than in group 2, (P=0.005) although the majority of these patients (7 of 10) had a previously diagnosed prostate cancer on TRUS-guided 12-core biopsy.
Our preliminary experience of mp-MRI suggests the detection of early stage prostate cancer with low-risk features yields potential candidates for active surveillance or focal targeted therapy. The MRI-TRUS fusion system increases diagnostic yield compared with cognitive MRI-directed TRUS-guided biopsy.
多参数磁共振成像（mpMRI）的可行性和诊断性能尚需进一步证实。本研究旨在评估 mpMRI 靶向活检早期前列腺癌（PCa）的作用。
连续选择 32 例经直肠超声（TRUS）引导下活检证实的符合低危标准且行主动监测的 PCa 患者，行 3T 磁共振成像（MRI）检查，均使用直肠内线圈。然后，根据靶向 mpMRI 指定感兴趣区（ROI）的方法将患者分为三组：第 1 组，使用基于 MRI 的坐标图（认知靶向）行 TRUS 引导下前列腺活检；第 2 组，使用 MyLabTwice 行 MRI 靶向 TRUS 引导下前列腺活检，该系统可将存档的 MRI 图像叠加到实时超声图像上，从而靶向活检 ROI（融合靶向）；第 3 组包括 PSA 水平升高的患者，或接受过放射治疗（2 例）的疑似局灶性 MRI 病变复发患者。这些患者使用导航系统 DynaTRIM 对可疑 ROI 行 MRI 引导下活检。
第 1 组的肿瘤检出率为 33.3%（10 例中有 3 例），第 2 组的肿瘤检出率显著更高，为 46.2%。第 1 组的敏感度和特异度分别为 45.5%和 33.3%，第 2 组分别为 61.9%和 20.8%。第 1 组的阳性预测值为 50.0%，第 2 组为 53.8%（P=0.04）。第 3 组的肿瘤检出率明显高于第 2 组（80%比 46.2%，P=0.005），尽管大多数患者（10 例中有 7 例）曾在经 TRUS 引导的 12 针活检中诊断为前列腺癌。
我们初步的 mpMRI 经验表明，对具有低危特征的早期前列腺癌进行检测可能为主动监测或局灶性靶向治疗提供潜在候选者。MRI-TRUS 融合系统与认知 MRI 引导的 TRUS 引导活检相比，可提高诊断效能。
