Department of Urology, University of Tampere and Tampere University Hospital, Box 2000, Tampere FIN-33521, Finland.
Br J Cancer. 2010 Feb 2;102(3):469-74. doi: 10.1038/sj.bjc.6605512. Epub 2010 Jan 5.
There is evidence that prostate cancer (PC) screening with prostate-specific antigen (PSA) serum test decreases PC mortality, but screening has adverse effects, such as a high false-positive (FP) rate. We investigated the proportion of FPs in a population-based randomised screening trial in Finland.
Finland is the largest centre in the European Randomized Study of Screening for Prostate Cancer. We have completed three screening rounds with a 4-year screening interval (mean follow-up time 9.2 years) using a PSA cutoff level of 4.0 ng ml(-1); in addition, men with PSA 3.0-3.9 and a positive auxiliary test were referred. An FP result was defined as a positive screening result without cancer in biopsy within 1 year from the screening test.
The proportion of FP screening results varied from 3.3 to 12.1% per round. Of the screened men, 12.5% had at least one FP during three rounds. The risk of next-round PC following an FP result was 12.3-19.7 vs 1.4-3.7% following a screen-negative result (depending on the screening round), risk ratio 3.6-9.9. More than half of the men with one FP result had another one at a subsequent screen. Men with an FP result were 1.5 to 2.0 times more likely to not participate in subsequent rounds compared with men with a normal screening result (21.6-29.6 vs 14.0-16.7%).
An FP result is a common adverse effect of PC screening and affects at least every eighth man screened repeatedly, even when using a relatively high cutoff level. False-positive men constitute a special group that receives unnecessary interventions but may harbour missed cancers. New strategies are needed for risk stratification in PC screening to minimise the proportion of FP men.
有证据表明，使用前列腺特异性抗原（PSA）血清检测进行前列腺癌（PC）筛查可降低 PC 死亡率，但筛查有不良反应，如高假阳性（FP）率。我们研究了芬兰一项基于人群的随机筛查试验中的 FP 比例。
芬兰是欧洲前列腺癌筛查随机研究的最大中心。我们已经完成了三轮筛查，筛查间隔为 4 年（平均随访时间为 9.2 年），使用 PSA 截断值为 4.0ng/ml；此外，PSA 为 3.0-3.9 且辅助检测阳性的男性也会被转诊。FP 结果定义为在筛查后 1 年内活检无癌症的阳性筛查结果。
每轮筛查的 FP 筛查结果比例为 3.3%至 12.1%。在接受筛查的男性中，有 12.5%在三轮筛查中至少有一次 FP。在一轮 FP 结果后发生下一轮 PC 的风险为 12.3%-19.7%，而在阴性筛查结果后为 1.4%-3.7%（取决于筛查轮次），风险比为 3.6-9.9。超过一半的单次 FP 结果的男性在随后的筛查中会再次出现 FP 结果。与正常筛查结果的男性相比，FP 结果的男性更有可能不参加随后的轮次，比例为 21.6%-29.6%比 14.0%-16.7%（21.6%-29.6%比 14.0%-16.7%）。
FP 结果是 PC 筛查的常见不良反应，即使使用相对较高的截断值，也会影响至少每 8 个接受重复筛查的男性。FP 男性构成一个特殊的群体，他们接受了不必要的干预，但可能错过了癌症。需要新的策略来对 PC 筛查进行风险分层，以尽量减少 FP 男性的比例。
