Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, Texas; Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas; Department of Mathematics, Technische Universitaet Muenchen, Munich, Germany.
Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, Texas.
J Urol. 2016 Aug;196(2):355-60. doi: 10.1016/j.juro.2016.03.011. Epub 2016 Mar 12.
We characterized the diagnostic properties of serial percent free prostate specific antigen in relation to prostate specific antigen in a multiethnic, multiracial cohort of healthy men.
A total of 6,982 percent free prostate specific antigen and prostate specific antigen measurements were obtained from participants in a greater than 12-year Texas screening study comprising 1,625 men who never underwent biopsy, 497 who underwent 1 or more biopsies negative for prostate cancer and 61 diagnosed with prostate cancer. We evaluated the ROC AUC of percent free prostate specific antigen and the proportion of patients with fluctuating values across multiple visits determined according to 2 thresholds (less than 15% vs 25%). The proportion of cancer cases in which percent free prostate specific antigen indicated a positive test before prostate specific antigen greater than 4 ng/ml did and the number of negative biopsies that would have been spared by negative percent free prostate specific antigen test results were calculated.
Percent free prostate specific antigen fluctuated around its threshold of less than 25% (less than 15%) in 38.3% (78.1%), 42.2% (20.9%), and 11.4% (25.7%) of patients never biopsied, and with negative and positive biopsies, respectively. At the same thresholds, percent free prostate specific antigen tested positive earlier than prostate specific antigen in 71.4% and 34.2% of cancer cases, respectively. Among men with multiple negative biopsies and PSA greater than 4 ng/ml, percent free PSA would have tested negative in 31.6% and 65.8%, respectively.
Percent free prostate specific antigen should accompany prostate specific antigen testing to potentially spare unnecessary biopsies or detect cancer earlier. When near the threshold, both tests should be repeated due to commonly observed fluctuation.
我们描述了游离前列腺特异性抗原（PSA）百分比与前列腺特异性抗原（PSA）在多民族、多种族健康男性队列中的诊断特性。
在一项持续时间超过 12 年的德克萨斯州筛查研究中，我们从 6982 名参与者中获得了游离 PSA 和 PSA 的测量值，其中 1625 名从未接受过活检，497 名接受过 1 次或多次前列腺癌阴性活检，61 名被诊断为前列腺癌。我们评估了游离 PSA 百分比的 ROC AUC 以及根据 2 个阈值（<15%比<25%）确定的多个就诊时游离 PSA 值波动的患者比例。计算了游离 PSA 百分比在 PSA>4ng/ml 之前指示阳性试验的癌症病例比例，以及通过阴性游离 PSA 试验结果可以避免的阴性活检数量。
在从未接受过活检的患者中，游离 PSA 百分比在其<25%（<15%）的阈值附近波动，分别为 38.3%（78.1%）、42.2%（20.9%）和 11.4%（25.7%），而在阴性和阳性活检患者中，分别为 42.2%（20.9%）和 11.4%（25.7%）。在相同的阈值下，游离 PSA 在 71.4%和 34.2%的癌症病例中比 PSA 更早呈阳性。在多次阴性活检和 PSA>4ng/ml 的男性中，游离 PSA 分别有 31.6%和 65.8%可能为阴性。
游离 PSA 应与 PSA 检测一起进行，以潜在地避免不必要的活检或更早发现癌症。当接近阈值时，由于经常观察到的波动，两种测试都应重复进行。
