Bergstralh Eric J, Roberts Rosebud O, Farmer Sara A, Slezak Jeffrey M, Lieber Michael M, Jacobsen Steven J
Division of Biostatistics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
Urology. 2007 Nov;70(5):936-41. doi: 10.1016/j.urology.2007.07.009.
The efficacy of screening for prostate cancer (PCa) with digital rectal examination (DRE) and prostate-specific antigen (PSA) measurement has not been proved in randomized clinical trials. In an earlier case-control study, we found that DRE might reduce PCa mortality. The present case-control study assessed the association between PSA and DRE testing and PCa mortality.
The case subjects included 74 Olmsted County residents who had died from 1992 to 2005 with PCa as the underlying cause of death. From 1 to 3 community control subjects (alive at time of case subject's death) were matched to each case subject. The medical records were reviewed to identify DREs and PSA determinations performed 0 to 5 years before the date the case was diagnosed (index date). Tests performed in the absence of symptoms were considered to be "screening tests." Conditional logistic regression analysis was used to estimate the odds ratios and 95% confidence intervals for the association of screening (defined in multiple ways) and PCa mortality.
From 1 to 5 years before the index date, control subjects were more likely than case subjects to have undergone a previous screening PSA test or DRE (81.3% versus 60.8%, P = 0.0005). The unadjusted odds ratio associated with a previous screening PSA test or DRE was 0.34 (95% confidence interval 0.18 to 0.63), and the odds ratio adjusted for potential confounders was 0.35 (95% confidence interval 0.17 to 0.71). PSA testing was frequently done in conjunction with DRE, making evaluation of the individual effects difficult.
The results of this case-control study suggest a potential benefit of screening by PSA testing and/or DRE on PCa mortality.
在随机临床试验中，通过直肠指检（DRE）和前列腺特异性抗原（PSA）检测筛查前列腺癌（PCa）的疗效尚未得到证实。在一项早期病例对照研究中，我们发现直肠指检可能降低PCa死亡率。本病例对照研究评估了PSA和DRE检测与PCa死亡率之间的关联。
病例组包括74名1992年至2005年间死于PCa的奥姆斯特德县居民，以PCa作为根本死因。为每个病例组匹配1至3名社区对照（在病例组死亡时存活）。查阅病历以确定在病例诊断日期（索引日期）前0至5年进行的直肠指检和PSA测定。在无症状情况下进行的检测被视为“筛查检测”。采用条件逻辑回归分析来估计多种定义方式下的筛查与PCa死亡率关联的比值比及95%置信区间。
在索引日期前1至5年，对照者比病例者更有可能曾接受过PSA筛查检测或直肠指检（81.3%对60.8%，P = 0.0005）。与之前的PSA筛查检测或直肠指检相关的未调整比值比为0.34（95%置信区间0.18至0.63），经潜在混杂因素调整后的比值比为0.35（95%置信区间0.17至0.71）。PSA检测经常与直肠指检同时进行，难以评估个体效应。
本病例对照研究结果提示，通过PSA检测和/或直肠指检进行筛查对PCa死亡率可能有益。
