Benecchi Luigi, Pieri Anna Maria, Destro Pastizzaro Carmelo, Potenzoni Michele
Department of Urology, Fidenza Hospital, Parma, Italy.
Urology. 2008 Mar;71(3):390-4. doi: 10.1016/j.urology.2007.10.021.
To compare different tools for evaluate prostate-specific antigen (PSA) kinetics before prostate biopsy, such as PSA velocity, PSA slope, natural logarithm PSA slope (lnPSA slope), and PSA doubling time (PSADT).
This study was conducted involving 325 male patients evaluated with transrectal ultrasound-guided biopsy of prostate. Patients with at least three consecutive PSA measurements taken in at least 24 months entered in the study. We estimated PSA slope from the slope of the least squares regression line fit to PSA versus time in years; PSA velocity was calculated as the running average of the rate of change during at least three consecutive assays. The acceleration of PSA (lnPSA slope) was calculated as the slope of lnPSA versus time, where ln is the natural logarithm. PSADT was calculated using the formula: PSADT = ln 2/(lnPSA slope).
We found a total of 74 cancers at the ultrasound guided prostate biopsies. At the receiver operating characteristic (ROC) analysis, lnPSA slope (area under the curve [AUC], 0.793) evidenced better results than PSA (AUC, 0.585; P <0.001), PSA velocity (AUC, 0.734; P <0.009), PSA slope (AUC, 0.752; P <0.043), and PSADT (AUC, 0.516; P <0.001).
The results for PSA, PSA velocity, PSA slope, and lnPSA slope were significantly higher in patients with prostate cancer than in controls. The results of the present study suggest that lnPSA slope may be useful for prostate cancer diagnosis. At the ROC analyses, the lnPSA slope AUC was better than that of PSA, PSA velocity, PSA slope, and PSADT.
比较前列腺活检前评估前列腺特异性抗原（PSA）动力学的不同工具，如PSA速率、PSA斜率、自然对数PSA斜率（lnPSA斜率）和PSA倍增时间（PSADT）。
本研究纳入325例接受经直肠超声引导下前列腺活检评估的男性患者。在至少24个月内进行了至少三次连续PSA测量的患者纳入研究。我们根据拟合PSA与时间（以年为单位）的最小二乘回归线的斜率估计PSA斜率；PSA速率计算为至少连续三次检测期间变化率的移动平均值。PSA加速度（lnPSA斜率）计算为lnPSA与时间的斜率，其中ln为自然对数。PSADT使用公式计算：PSADT = ln 2 /（lnPSA斜率）。
在超声引导下的前列腺活检中，我们共发现74例癌症。在受试者操作特征（ROC）分析中，lnPSA斜率（曲线下面积[AUC]，0.793）显示出比PSA（AUC，0.585；P <0.001）、PSA速率（AUC，0.734；P <0.009）、PSA斜率（AUC，0.752；P <0.043）和PSADT（AUC，0.516；P <0.001）更好的结果。
前列腺癌患者的PSA、PSA速率、PSA斜率和lnPSA斜率结果显著高于对照组。本研究结果表明，lnPSA斜率可能有助于前列腺癌的诊断。在ROC分析中，lnPSA斜率的AUC优于PSA、PSA速率、PSA斜率和PSADT。
