PURPOSE The PRECISE score estimates the likelihood of radiological progression in patients on active surveillance (AS) for prostate cancer (PCa) with serial multiparametric magnetic resonance imaging (mpMRI). A PRECISE score of 1 or 2 denotes radiological regression, PRECISE 3 indicates stability and PRECISE 4 or 5 implies progression. We evaluated the inter-reader reproducibility of different apparent diffusion coefficient (ADC) calculations and their relationship to the PRECISE score. MATERIAL AND METHODS Baseline and follow-up scans (on the same MR systems) of 30 patients with visible lesions from two different institutions (University College London and Sapienza University of Rome) were analysed by two radiologists (one from each site). The PRECISE score was initially assessed in consensus. At least six weeks later, to reduce the likelihood of being influenced by the consensus PRECISE reading, each radiologist independently calculated ADC for the following: lesion, non-cancerous tissue and urine in the bladder. Normalised ADC ratios were calculated with respect to normal prostatic tissue (npADC) and urine. Spearman's correlation (ρ), intraclass correlation coefficients (ICC), differences in ADC and ROC curves were computed. RESULTS Interobserver reproducibility was very good (ρ > 0.8; ICC > 0.90). Lesion ADC (0.91 vs 0.73 × 10-3 mm2/s; p=0.025) and npADC ratio (0.68 vs 0.53; p=0.012) at follow-up mpMRI were different between patients with radiological regression or stability vs progression. Cut-offs of 0.77 × 10-3 mm2/s (lesion ADC) and 0.59 (npADC ratio) could differentiate the two groups (area under the curve: 0.74 and 0.77, respectively). CONCLUSION The ADC, npADC ratio and the PRECISE score should be recorded for MRI-based AS.

中文翻译：

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男性主动监测前列腺癌的 DWI 和 PRECISE 标准：不同 ADC 计算的多中心初步经验。


目的 PRECISE 评分评估通过连续多参数磁共振成像 (mpMRI) 进行前列腺癌 (PCa) 主动监测 (AS) 的患者放射学进展的可能性。 PRECISE 分数为 1 或 2 表示放射学回归，PRECISE 3 表示稳定，PRECISE 4 或 5 表示进展。我们评估了不同表观扩散系数 (ADC) 计算的读者间再现性及其与 PRECISE 分数的关系。材料和方法 来自两个不同机构（伦敦大学学院和罗马萨皮恩扎大学）的 30 名具有可见病变的患者的基线和后续扫描（在相同的 MR 系统上）由两名放射科医生（每个地点一名）进行了分析。 PRECISE 分数最初是经过一致评估的。至少六周后，为了减少受到共识精确读数影响的可能性，每位放射科医生独立计算了以下各项的 ADC：病变、非癌组织和膀胱中的尿液。根据正常前列腺组织 (npADC) 和尿液计算标准化 ADC 比率。计算 Spearman 相关性 (ρ)、组内相关系数 (ICC)、ADC 和 ROC 曲线的差异。结果 观察者间的重现性非常好（ρ > 0.8；ICC > 0.90）。随访 mpMRI 中病变 ADC（0.91 vs 0.73 × 10-3 mm2/s；p=0.025）和 npADC 比率（0.68 vs 0.53；p=0.012）在放射学消退或稳定与进展患者之间存在差异。 0.77 × 10-3 mm2/s（病变 ADC）和 0.59（npADC 比率）的截止值可以区分两组（曲线下面积：分别为 0.74 和 0.77）。结论 对于基于 MRI 的 AS，应记录 ADC、npADC 比率和 PRECISE 评分。