Pinsky Paul F, Kramer Barnett S, Crawford E David, Grubb Robert L, Urban Donald A, Andriole Gerald L, Chia David, Levin David L, Gohagan John K
Division of Cancer Prevention, National Cancer Institute, Bethedsa, Maryland, USA.
Urology. 2006 Aug;68(2):352-6. doi: 10.1016/j.urology.2006.02.026.
Prostate volume correlates both with prostate-specific antigen (PSA) values and with the presence of benign prostatic hyperplasia (BPH). Here we examine the relationship between prostate volume and PSA level in a large, geographically diverse sample of men undergoing prostate cancer screening.
We followed 35,323 men enrolled in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Each man was screened with digital rectal examination (DRE) and PSA levels for up to 4 years. Prostate volume was estimated by DRE performed by trained examiners at the PLCO sites. Linear and logistic regression was used to assess the effect of prostate volume and age on PSA levels. Regression coefficients were adjusted for the effect of prostate volume measurement error.
Prostate volume estimated by DRE showed considerable measurement error. Averaging volume over screening visits and accounting for examiner bias greatly reduced this error. Linear regression analysis showed a slope of 0.030/cm3 of log PSA on prostate volume when correcting for measurement error (95% confidence interval [CI], 0.029 to 0.031). Age was independently associated with (log) PSA, with a slope of 0.022 per year. Logistic regression analysis of the risk of having an elevated PSA value (exceeding 4 ng/mL) showed an odds ratio of 1.9 (95% CI, 1.8 to 2.0) associated with a 10 cm3 increase in prostate volume. The correlation of log PSA and prostate volume was 0.37. Prostate volume was not correlated with body mass index and showed weak correlation (r = 0.14) with age.
Prostate volume and age are independently associated with increased PSA levels in a population of men undergoing screening.
前列腺体积与前列腺特异性抗原（PSA）值以及良性前列腺增生（BPH）的存在均相关。在此，我们在一个地域分布广泛的接受前列腺癌筛查的男性大样本中研究前列腺体积与PSA水平之间的关系。
我们对参与前列腺、肺、结肠和卵巢（PLCO）癌筛查试验的35323名男性进行了随访。每位男性接受了长达4年的直肠指检（DRE）和PSA水平检测。前列腺体积由PLCO各站点经过培训的检查者通过DRE进行估算。采用线性回归和逻辑回归来评估前列腺体积和年龄对PSA水平的影响。对回归系数进行了调整，以校正前列腺体积测量误差的影响。
通过DRE估算的前列腺体积显示出相当大的测量误差。对多次筛查访视的体积进行平均并考虑检查者偏差可大大减少此误差。校正测量误差后，线性回归分析显示前列腺体积每增加1cm³，log PSA的斜率为0.030（95%置信区间[CI]，0.029至0.031）。年龄与（log）PSA独立相关，斜率为每年0.022。对PSA值升高（超过4 ng/mL）风险的逻辑回归分析显示，前列腺体积增加10 cm³，优势比为1.9（95%CI，1.8至2.0）。log PSA与前列腺体积的相关性为0.37。前列腺体积与体重指数不相关，与年龄呈弱相关性（r = 0.14）。
在接受筛查的男性人群中，前列腺体积和年龄与PSA水平升高独立相关。
