Department of Urology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Department of Urology, Kanta-Häme Central Hospital, Hämeenlinna, Finland.
J Urol. 2017 Jul;198(1):50-57. doi: 10.1016/j.juro.2017.01.048. Epub 2017 Jan 16.
Screening for prostate cancer remains controversial, although ERSPC (European Randomized Study of Screening for Prostate Cancer) showed a 21% relative reduction in prostate cancer mortality. The Finnish Randomized Study of Screening for Prostate Cancer, which is the largest component of ERSPC, demonstrated a statistically nonsignificant 16% mortality benefit in a separate analysis. The purpose of this study was to estimate the degree of contamination in the control arm of the Finnish trial.
Altogether 48,295 and 31,872 men were randomized to the control and screening arms, respectively. The screening period was 1996 to 2007. The extent of prostate specific antigen testing was analyzed retrospectively using laboratory databases. The incidence of T1c prostate cancer (impalpable prostate cancer detected by elevated prostate specific antigen) was determined from the national Finnish Cancer Registry.
Approximately 1.4% of men had undergone prostate specific antigen testing 1 to 3 years before randomization. By the first 4, 8 and 12 years of followup 18.1%, 47.7% and 62.7% of men in the control arm had undergone prostate specific antigen testing at least once and in the screening arm the proportions were 69.8%, 81.1% and 85.2%, respectively. The cumulative incidence of T1c prostate cancer was 6.1% in the screening arm and 4.5% in the control arm (RR 1.21, 95% CI 1.13-1.30).
A large proportion of men in the control arm had undergone a prostate specific antigen test during the 15-year followup. Contamination is likely to dilute differences in prostate cancer mortality between the arms in the Finnish screening trial.
尽管 ERSPC（前列腺癌筛查的欧洲随机研究）显示前列腺癌死亡率相对降低了 21%，但前列腺癌筛查仍存在争议。芬兰前列腺癌筛查随机研究是 ERSPC 的最大组成部分，其单独分析显示死亡率有统计学上无显著意义的 16%获益。本研究旨在估计芬兰试验对照组的污染程度。
共有 48295 名和 31872 名男性分别随机分配到对照组和筛查组。筛查期为 1996 年至 2007 年。使用实验室数据库回顾性分析前列腺特异性抗原检测的程度。通过全国芬兰癌症登记处确定 T1c 前列腺癌（由升高的前列腺特异性抗原检测到的无法触及的前列腺癌）的发病率。
大约 1.4%的男性在随机分组前 1 至 3 年内进行了前列腺特异性抗原检测。在对照组的前 4、8 和 12 年随访中，分别有 18.1%、47.7%和 62.7%的男性至少进行了一次前列腺特异性抗原检测，而在筛查组中，这一比例分别为 69.8%、81.1%和 85.2%。筛查组的 T1c 前列腺癌累积发病率为 6.1%，对照组为 4.5%（RR 1.21，95%CI 1.13-1.30）。
在 15 年的随访中，对照组中有很大一部分男性接受了前列腺特异性抗原检测。污染可能会稀释芬兰筛查试验中两组之间前列腺癌死亡率的差异。
