Shepherd Leah, Borges Álvaro H, Ravn Lene, Harvey Richard, Bower Mark, Grulich Andrew, Silverberg Michael, Kronborg Gitte, Galli Massimo, Kirk Ole, Lundgren Jens, Mocroft Amanda
Research Department of Infection and Population Health, University College London, London, UK.
Centre for Health & Infectious Disease Research (CHIP), Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
Antivir Ther. 2016;21(6):529-534. doi: 10.3851/IMP3026. Epub 2016 Jan 29.
It is common practice to use prostate specific antigen (PSA) ≥4.0 ng/ml as a clinical indicator for men at risk of prostate cancer (PCa), however, this is unverified in HIV+ men. We aimed to describe kinetics and predictive value of PSA for PCa in HIV+ men.
A nested case control study of 21 men with PCa and 40 matched-controls within EuroSIDA was conducted. Prospectively stored plasma samples before PCa (or matched date in controls) were measured for the following markers: total PSA (tPSA), free PSA (fPSA), testosterone and sex hormone binding globulin (SHBG). Conditional logistic regression models investigated associations between markers and PCa. Mixed models were used to describe kinetics. Sensitivity and specificity of using tPSA >4 ng/ml to predict PCa was calculated. Receiver operating characteristic curves were used to identify optimal cutoffs in HIV+ men for total PSA.
61 HIV+ men were included with a median 6 (IQR 2-9) years follow-up. Levels of tPSA increased by 13.7% per year (95% CI 10.3, 17.3) in cases, but was stable in controls (-0.4%; 95% CI -2.5, 1.7). Elevated PSA was associated with higher odds of PCa at first (OR for twofold higher 4.7; 95% CI 1.7, 12.9; P<0.01) and last sample (8.1; 95% CI 1.1, 58.9; P=0.04). A similar relationship was seen between fPSA and PCa. Testosterone and SHBG level were not associated with PCa. tPSA level >4 ng/ml had 99% specificity and 38% sensitivity. The optimal PSA cutoff was 1.5 ng/ml overall (specificity =84%, sensitivity =81%).
PSA was highly predictive of PCa in HIV+ men; however, the commonly used PSA>4 ng/ml to indicate high PCa risk was not sensitive in our population and use of the lower cutoff of PSA>1.5 ng/ml warrants consideration.
将前列腺特异性抗原（PSA）≥4.0 ng/ml用作前列腺癌（PCa）风险男性的临床指标是常见做法，然而，在HIV阳性男性中这一点未经证实。我们旨在描述HIV阳性男性中PSA对PCa的动力学及预测价值。
在欧洲艾滋病临床研究数据库（EuroSIDA）中对21例PCa男性和40例匹配对照进行了巢式病例对照研究。前瞻性收集PCa发生前（或对照中的匹配日期）储存的血浆样本，检测以下标志物：总PSA（tPSA）、游离PSA（fPSA）、睾酮和性激素结合球蛋白（SHBG）。条件逻辑回归模型研究标志物与PCa之间的关联。混合模型用于描述动力学。计算使用tPSA>4 ng/ml预测PCa的敏感性和特异性。采用受试者工作特征曲线确定HIV阳性男性中总PSA的最佳临界值。
纳入61例HIV阳性男性，中位随访6（IQR 2 - 9）年。病例组中tPSA水平每年升高13.7%（95% CI 10.3，17.3），而对照组稳定（-0.4%；95% CI -2.5，1.7）。首次（两倍升高时的OR为4.7；95% CI 1.7，12.9；P<0.01）和末次样本时（8.1；95% CI 1.1，58.9；P = 0.04），PSA升高与PCa的较高几率相关。fPSA与PCa之间也观察到类似关系。睾酮和SHBG水平与PCa无关。tPSA水平>4 ng/ml的特异性为99%，敏感性为38%。总体最佳PSA临界值为1.5 ng/ml（特异性 = 84%，敏感性 = 81%）。
PSA对HIV阳性男性中的PCa具有高度预测性；然而，常用的PSA>4 ng/ml来表明高PCa风险在我们的人群中不敏感，考虑使用较低的PSA临界值>1.5 ng/ml是有必要的。
