Vasarainen Hanna, Salman Jolanda, Salminen Heidi, Valdagni Riccardo, Pickles Tom, Bangma Chris, Roobol Monique J, Rannikko Antti
Department of Urology, Peijas Hospital, Helsinki University Central Hospital and University of Helsinki, P.O. Box 900, 00029, Helsinki, Finland.
Department of Urology, Erasmus Medical Center, Rotterdam, The Netherlands.
World J Urol. 2015 Nov;33(11):1735-40. doi: 10.1007/s00345-015-1542-3. Epub 2015 Mar 31.
To evaluate the utility of percentage of free serum PSA (%fPSA) as a predictor of adverse rebiopsy findings, treatment change and radical prostatectomy (RP) findings in a prospective active surveillance (AS) trial.
Patients enrolled in the global PRIAS study with baseline %fPSA available were included. Putative baseline predictors (e.g. PSA, %fPSA) of adverse rebiopsy findings were explored using logistic regression analysis. Association of variables with treatment change and RP findings over time were evaluated with Cox regression analysis. Active treatment-free survival was assessed with a Kaplan-Meier method.
Of 3701 patients recruited to PRIAS, 939 had %fPSA measured at study entry. Four hundred and thirty-eight of them had %fPSA available after 1 year. Median follow-up was 17.2 months. First rebiopsy results were available for 595 patients and of those, 144 (24.2 %) had adverse findings. A total of 283 (30.1 %) patients discontinued surveillance, of those 181 (64.0 %) due to protocol-based reasons. Although median %fPSA values were significantly lower in patients who changed treatment, according to the multivariate regression analysis, initial %fPSA value was not predictive for treatment change or adverse rebiopsy findings. However, the probability of discontinuing AS was significantly lower in patients with "favourable" initial %fPSA characteristics and %fPSA during follow-up (initial %fPSA ≥15 and positive %fPSA velocity) compared to those with "adverse" %fPSA characteristics (initial %fPSA <15 and negative %fPSA velocity).
Diagnostic %fPSA provides no additional prognostic value when compared to other predictors already in use in AS protocols. However, %fPSA velocity during surveillance may aid in predicting the probability for future treatment change.
在一项前瞻性主动监测（AS）试验中，评估游离血清前列腺特异性抗原百分比（%fPSA）作为不良重复活检结果、治疗改变及根治性前列腺切除术（RP）结果预测指标的效用。
纳入全球PRIAS研究中可获得基线%fPSA的患者。使用逻辑回归分析探索不良重复活检结果的假定基线预测指标（如PSA、%fPSA）。通过Cox回归分析评估变量与随时间变化的治疗改变及RP结果之间的关联。采用Kaplan-Meier方法评估无主动治疗生存期。
在招募至PRIAS的3701例患者中，939例在研究入组时测量了%fPSA。其中438例在1年后仍有%fPSA数据。中位随访时间为17.2个月。595例患者有首次重复活检结果，其中144例（24.2%）有不良结果。共有283例（30.1%）患者停止监测，其中181例（64.0%）因符合方案规定的原因。尽管改变治疗的患者中位%fPSA值显著更低，但根据多变量回归分析，初始%fPSA值并不能预测治疗改变或不良重复活检结果。然而，与具有“不良”%fPSA特征（初始%fPSA<15且%fPSA变化速度为负）的患者相比，具有“有利”初始%fPSA特征及随访期间%fPSA（初始%fPSA≥15且%fPSA变化速度为正）的患者停止AS的概率显著更低。
与AS方案中已使用的其他预测指标相比，诊断性%fPSA没有额外的预后价值。然而，监测期间的%fPSA变化速度可能有助于预测未来治疗改变的概率。
