Memorial Sloan-Kettering Cancer Center, Department of Epidemiology and Biostatistics, 307 E. 63rd St., New York, NY 10021, USA.
Eur Urol. 2009 Nov;56(5):753-60. doi: 10.1016/j.eururo.2009.07.047. Epub 2009 Aug 7.
It has been suggested that changes in prostate-specific antigen (PSA) over time (ie, PSA velocity [PSAV]) aid prostate cancer detection. Some guidelines do incorporate PSAV cut points as an indication for biopsy.
To evaluate whether PSAV enhances prediction of biopsy outcome in a large, representative, population-based cohort.
DESIGN, SETTING, AND PARTICIPANTS: There were 2742 screening-arm participants with PSA <3 ng/ml at initial screening in the European Randomized Study of Screening for Prostate Cancer in Rotterdam, Netherlands, or Göteborg, Sweden, and who were subsequently biopsied during rounds 2-6 due to elevated PSA.
Total, free, and intact PSA and human kallikrein 2 were measured for 1-6 screening rounds at intervals of 2 or 4 yr. We created logistic regression models to predict prostate cancer based on age and PSA, with or without free-to-total PSA ratio (%fPSA). PSAV was added to each model and any enhancement in predictive accuracy assessed by area under the curve (AUC).
PSAV led to small enhancements in predictive accuracy (AUC of 0.569 vs 0.531; 0.626 vs 0.609 if %fPSA was included), although not for high-grade disease. The enhancement depended on modeling a nonlinear relationship between PSAV and cancer. There was no benefit if we excluded men with higher velocities, which were associated with lower risk. These results apply to men in a screening program with elevated PSA; men with prior negative biopsy were not evaluated in this study.
In men with PSA of about ≥3 ng/ml, we found little justification for formal calculation of PSAV or for use of PSAV cut points to determine biopsy. Informal assessment of PSAV will likely aid clinical judgment, such as a sudden rise in PSA suggesting prostatitis, which could be further evaluated before biopsy.
有人认为,前列腺特异性抗原(PSA)随时间的变化(即 PSA 速度 [PSAV])有助于前列腺癌的检测。一些指南确实将 PSAV 切点纳入活检指征。
在一个大型、代表性的基于人群的队列中评估 PSAV 是否增强了对活检结果的预测。
设计、地点和参与者:在荷兰鹿特丹和瑞典哥德堡的欧洲前列腺癌筛查随机研究中,有 2742 名筛查组参与者在初次筛查时 PSA<3ng/ml,随后由于 PSA 升高,在第 2-6 轮期间进行了活检。
在 2 或 4 年的间隔内,对 1-6 轮筛查进行了总 PSA、游离 PSA 和完整 PSA 以及人激肽释放酶 2 的测量。我们创建了基于年龄和 PSA 的预测前列腺癌的逻辑回归模型,包括或不包括游离 PSA 与总 PSA 之比(%fPSA)。在每个模型中添加 PSAV,并通过曲线下面积(AUC)评估任何预测准确性的提高。
PSAV 导致预测准确性略有提高(AUC 从 0.531 提高到 0.569;如果包括 %fPSA,则从 0.609 提高到 0.626),但对高级别疾病没有提高。这种提高取决于对 PSAV 与癌症之间的非线性关系进行建模。如果排除与低风险相关的较高速度的男性,则没有获益。这些结果适用于 PSA 升高的筛查计划中的男性;本研究未评估先前阴性活检的男性。
在 PSA 约为≥3ng/ml 的男性中,我们发现没有充分的理由正式计算 PSAV 或使用 PSAV 切点来确定活检。对 PSAV 的非正式评估可能有助于临床判断,例如 PSA 突然升高提示前列腺炎,可以在活检前进一步评估。