Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA.
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Prostate Cancer Prostatic Dis. 2021 Jun;24(2):457-464. doi: 10.1038/s41391-020-00297-x. Epub 2020 Nov 9.
The validated Stockholm3 test is used to improve PC detection. Stockholm3, however, was developed using systematic biopsies. We aimed to assess Stockholm3 operating performance when using MRI-targeted biopsies for PC detection.
A prospective cohort of 532 men was considered for prostate biopsy during 2016-2017. All men underwent Stockholm3 testing and MRI before biopsy. All PIRADs ≥3 lesion underwent targeted biopsy; all men underwent systematic biopsy. The primary outcome was ISUP Grade Group ≥2 (GG ≥ 2) PC. Detection strategies included: (1) systematic biopsies alone, (2) targeted biopsies alone, (3) targeted with associated systematic biopsies for MRI+, and (4) all biopsies in all men. For each strategy, the Stockholm3 operating characteristics were assessed with discrimination, calibration, and decision curve analysis (DCA).
Median age was 65 years, median PSA was 6.2 ng/mL, median Stockholm3 score was 16.5%, and overall detection of GG ≥ 2 PC was 36% (193/532). Stockholm3 showed accurate discrimination for separating GG ≥ 2 cancer from benign and GG1, with an area under the curve of 0.84-0.86 depending on the biopsy strategy. Calibration analysis showed that Stockholm3 underestimated risks for GG ≥ 2 PC risk using MRI-targeted biopsies: there was a net benefit over biopsies in all men for Stockholm3 at risk thresholds varying from >3% in systematic biopsies to >15% in targeted with systematic biopsies in MRI+ men. When using a Stockholm3 score of >10% cutoff, a range of 32-38% of biopsies could be avoided while missing 5-11% of GG ≥ 2 PC and 0-3% of GG ≥ 3 PC.
Stockholm3 shows high discriminatory performance in an MRI-targeted biopsy setting, however risks are underpredicted due to MRI-targeted biopsies being more sensitive than the systematic biopsies for which Stockholm3 was developed. Stockholm3, along with any risk prediction model developed for systematic prostate biopsy decisions, will need recalibration for optimal use in an MRI-driven biopsy setting.
经过验证的 Stockholm3 测试用于提高 PC 的检测率。然而，Stockholm3 是使用系统活检开发的。我们旨在评估使用 MRI 靶向活检检测 PC 时，Stockholm3 的操作性能。
2016 年至 2017 年期间，对 532 名男性进行了前列腺活检的前瞻性队列研究。所有男性在活检前均接受了 Stockholm3 测试和 MRI。所有 PIRADs≥3 病变均接受靶向活检；所有男性均接受系统活检。主要结局是 ISUP 分级组≥2（GG≥2）PC。检测策略包括：（1）仅系统活检，（2）仅靶向活检，（3）MRI+ 时靶向联合系统活检，（4）所有男性的所有活检。对于每种策略，使用判别分析、校准和决策曲线分析（DCA）评估 Stockholm3 的操作特性。
中位年龄为 65 岁，中位 PSA 为 6.2ng/mL，中位 Stockholm3 评分为 16.5%，总体 GG≥2 PC 的检出率为 36%（193/532）。Stockholm3 对区分 GG≥2 癌与良性和 GG1 的准确性较高，取决于活检策略，曲线下面积在 0.84-0.86 之间。校准分析表明，使用 MRI 靶向活检时，Stockholm3 低估了 GG≥2 PC 风险：在风险阈值从系统活检中的>3%到 MRI+ 男性中靶向联合系统活检中的>15%，Stockholm3 相对于所有男性的活检均有净获益。当使用>10%的 Stockholm3 评分截断值时，活检范围可减少 32-38%，同时错过 5-11%的 GG≥2 PC 和 0-3%的 GG≥3 PC。
Stockholm3 在 MRI 靶向活检环境中具有较高的判别性能，然而，由于 MRI 靶向活检比为其开发的系统活检更敏感，因此风险被低估。Stockholm3 与为系统前列腺活检决策开发的任何风险预测模型一样，需要进行重新校准，以便在 MRI 驱动的活检环境中得到最佳应用。
