Department of Urology, Erasmus MC, Rotterdam, The Netherlands.
Eur Urol. 2010 Jun;57(6):921-7. doi: 10.1016/j.eururo.2010.02.003. Epub 2010 Feb 13.
Novel markers for prostate cancer (PCa) detection are needed. Total prostate-specific antigen (tPSA) and percent free prostate-specific antigen (%fPSA=tPSA/fPSA) lack diagnostic specificity.
To evaluate the use of prostate-specific antigen (PSA) isoforms p2PSA and benign prostatic hyperplasia-associated PSA (BPHA).
DESIGN, SETTING, AND PARTICIPANTS: Our study included 405 serum samples from the Rotterdam arm of the European Randomised Study of Screening for Prostate Cancer and 351 samples from the Urology Department of Innsbruck Medical University.
BPHA, tPSA, fPSA, and p2PSA levels were measured by Beckman-Coulter Access Immunoassay. In addition, the Beckman Coulter Prostate Health Index was calculated: phi=(p2PSA/fPSA)×√(tPSA).
The p2PSA and phi levels differed significantly between men with and without PCa. No difference in BPHA levels was observed. The highest PCa predictive value in both cohorts was achieved by phi with areas under the curve (AUCs) of 0.750 and 0.709, a significant increase compared to tPSA (AUC: 0.585 and 0.534) and %fPSA (AUC: 0.675 and 0.576). Also, %p2PSA (p2PSA/fPSA) showed significantly higher AUCs compared to tPSA and %fPSA (AUC: 0.716 and 0.695, respectively). At 95% and 90% sensitivity, the specificities of phi were 23% and 31% compared to 10% and 8% for tPSA, respectively. In both cohorts, multivariate analysis showed a significant increase in PCa predictive value after addition of p2PSA to a model consisting of tPSA and fPSA (increase in AUC from 0.675 to 0.755 and from 0.581 to 0.697, respectively). Additionally, the specificity at 95% sensitivity increased from 8% to 24% and 7% to 23%, respectively. Furthermore, %p2PSA, phi, and the model consisting of tPSA and fPSA with or without the addition of p2PSA missed the least of the tumours with a biopsy or pathologic Gleason score ≥7 at 95% and 90% sensitivity.
This study shows significant increases in PCa predictive value and specificity of phi and %p2PSA compared to tPSA and %fPSA. p2PSA has limited additional value in identifying aggressive PCa (Gleason score ≥7).
需要新的前列腺癌（PCa）检测标志物。总前列腺特异性抗原（tPSA）和游离前列腺特异性抗原百分比（%fPSA=tPSA/fPSA）缺乏诊断特异性。
评估前列腺特异性抗原（PSA）同工型 p2PSA 和良性前列腺增生相关 PSA（BPHA）的应用。
设计、地点和参与者：我们的研究包括来自欧洲前列腺癌筛查随机研究的鹿特丹组的 405 份血清样本和因斯布鲁克医科大学泌尿科的 351 份样本。
通过贝克曼库尔特 Access 免疫分析测量 BPHA、tPSA、fPSA 和 p2PSA 水平。此外，还计算了贝克曼库尔特前列腺健康指数：phi=(p2PSA/fPSA)×√(tPSA)。
PCa 患者和非 PCa 患者的 p2PSA 和 phi 水平有显著差异。BPHA 水平无差异。在两个队列中，phi 的预测 PCa 价值最高，曲线下面积（AUCs）分别为 0.750 和 0.709，与 tPSA（AUC：0.585 和 0.534）和 %fPSA（AUC：0.675 和 0.576）相比有显著提高。此外，与 tPSA 和 %fPSA 相比，%p2PSA（p2PSA/fPSA）的 AUC 也显著更高（AUC：0.716 和 0.695）。在 95%和 90%的敏感性时，phi 的特异性分别为 23%和 31%，而 tPSA 的特异性分别为 10%和 8%。在两个队列中，多变量分析显示，在 tPSA 和 fPSA 模型中加入 p2PSA 后，PCa 的预测价值显著增加（AUC 分别从 0.675 增加到 0.755 和从 0.581 增加到 0.697）。此外，95%敏感性时的特异性分别从 8%增加到 24%和从 7%增加到 23%。此外，在 95%和 90%的敏感性时，%p2PSA、phi 和包含 tPSA 和 fPSA 的模型，无论是否添加 p2PSA，漏诊的活检或病理 Gleason 评分≥7 的肿瘤最少。
与 tPSA 和 %fPSA 相比，phi 和 %p2PSA 对 PCa 的预测价值和特异性有显著提高。p2PSA 在识别侵袭性 PCa（Gleason 评分≥7）方面的附加价值有限。
