Department of Urology, The Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA.
J Urol. 2012 Oct;188(4):1131-6. doi: 10.1016/j.juro.2012.06.009. Epub 2012 Aug 15.
Previous studies have suggested an association between [-2]proPSA expression and prostate cancer detection. Less is known about the usefulness of this marker in following patients with prostate cancer on active surveillance. Thus, we examined the relationship between [-2]proPSA and biopsy results in men enrolled in an active surveillance program.
In 167 men from our institutional active surveillance program we used Cox proportional hazards models to examine the relationship between [-2]proPSA and annual surveillance biopsy results. The outcome of interest was biopsy reclassification (Gleason score 7 or greater, more than 2 positive biopsy cores or more than 50% involvement of any core with cancer). We also examined the association of biopsy results with total prostate specific antigen, %fPSA, [-2]proPSA/%fPSA and the Beckman Coulter Prostate Health Index phi ([-2]proPSA/free prostate specific antigen) × (total prostate specific antigen)(½)).
While on active surveillance (median time from diagnosis 4.3 years), 63 (37.7%) men demonstrated biopsy reclassification based on the previously mentioned criteria, including 28 (16.7%) of whom had reclassification based on Gleason score upgrading (Gleason score 7 or greater). Baseline and longitudinal %fPSA, %[-2]proPSA, [-2]proPSA/%fPSA and phi measurements were significantly associated with biopsy reclassification, and %[-2]proPSA and phi provided the greatest predictive accuracy for high grade cancer.
In men on active surveillance, measures based on [-2]proPSA such as phi appear to provide improved prediction of biopsy reclassification during followup. Additional validation is warranted to determine whether clinically useful thresholds can be defined, and to better characterize the role of %[-2]proPSA and phi in conjunction with other markers in monitoring patients enrolled in active surveillance.
之前的研究表明，[-2]proPSA 的表达与前列腺癌的检出有关。关于这种标志物在对接受主动监测的前列腺癌患者的随访中的作用，人们知之甚少。因此，我们检查了 [-2]proPSA 与参加主动监测项目的男性活检结果之间的关系。
在我们机构的主动监测项目的 167 名男性中，我们使用 Cox 比例风险模型来检查 [-2]proPSA 与年度监测活检结果之间的关系。感兴趣的结果是活检再分类（Gleason 评分 7 或更高、2 个以上阳性活检核心或任何核心癌症浸润超过 50%）。我们还检查了活检结果与总前列腺特异性抗原、%fPSA、[-2]proPSA/%fPSA 和贝克曼库尔特前列腺健康指数 phi（[-2]proPSA/游离前列腺特异性抗原）×（总前列腺特异性抗原）（½）之间的相关性。
在主动监测期间（从诊断到中位数时间为 4.3 年），63 名（37.7%）男性根据上述标准显示活检再分类，其中 28 名（16.7%）男性根据 Gleason 评分升级（Gleason 评分 7 或更高）进行了再分类。基线和纵向 %fPSA、%[-2]proPSA、[-2]proPSA/%fPSA 和 phi 测量与活检再分类显著相关，%[-2]proPSA 和 phi 对高级别癌症提供了最大的预测准确性。
在接受主动监测的男性中，基于 [-2]proPSA 的指标，如 phi，似乎可以更好地预测随访期间的活检再分类。需要进一步验证以确定是否可以定义临床有用的阈值，并更好地描述 %[-2]proPSA 和 phi 与其他标志物在监测参加主动监测的患者中的作用。
