Letter to the EditorProstate-specific antigen screening for prostate cancer:Why so much controversy?As prostate cancer remains the second leading cause of cancer deaths in men with238590new cases and29720 deaths estimated for2013in the USA alone,1it seems important to further examine the data responsible for the surprising recommendations against prostate cancer screen-ing.As prostate cancer progresses with no symptoms,these negative opinions need to be reconciled with the recognized fact that without screening,the majority of men will reach the advanced metastatic stage before being diagnosed,thus losing the possibility of a cure and regressing40years in the approach to prostate cancer diagnosis and treament.An update at11years of follow up of the European Ran-domized Study of Screening for Prostate Cancer(ERSPC) shows an overall21%reduction in the rate of prostate cancer deaths,with a relative risk reduction of38%during years 10and11.2In the Quebec study,at a median of7.93years of follow up,a62%decrease in prostate cancer deaths was observed.3Contrary to the European and Quebec studies,the USA Prostate,Lung,Colon and Ovarian Cancer(PLCO)study reported no influence of screening on deaths from prostate cancer.4Examination of the PLCO trial,however,shows that 79%of men in the so-called“control”group at year5had a previous prostate-specific antigen(PSA)test compared with91%in the screened group.In fact,just13%of men reported never having a PSA or digital rectal examina-tion test in the intended“control”group.In short,it has been estimated that the PLCO trial had up to85%of men screened in the“control”arm where no man should have been screened.With such a high rate of contamination of men screened in the“control”group,the PLCO study did not have the statistical power to provide any meaningful information. In fact,it was already too late in1993to start a screening trial in the USA,as too many men had already been screened.It can be added that the important benefits of screening observed in the European study were achieved using a less than optimal4-year PSA screening interval,which misses a significant number of cancers,whereas the Quebec study used the1-year interval,thus potentially explaining the62% benefit observed in favor of screening in the Quebec trial3 compared with38%in years10and11in the European study.2In fact,only men having a PSA below1.0ng/mL can be screened every4years with no significant negative impact on the time of cancer diagnosis.From the aforementioned facts,it seems reasonable to suggest that the USA study4cannot be used to support any recommendation about screening.Recommendations about screening should only be based on data obtained in clinical trials that have sufficient statistical power,and are free of seriousflaws and bias;the absence of a true control group being a fundamental issue.Although some criticism can be expressed,the best conditions for a screening evaluation have been those of the European and Quebec trials,which both show a very important reduction of prostate cancer deaths by screening.Fernand Labrie M.D.,Ph.D.Laval University,Quebec,Quebec,Canadaflabrie@attglobal.netConflict of interestNone declared.References1Siegel R,Naishadham D,Jemal A.Cancer statistics,2013.CA Cancer J.Clin. 2013;63:11–30.2Schroder FH,Hugosson J,Roobol MJ et al.Prostate-cancer mortality at11 years of follow-up.N.Engl.J.Med.2012;366:981–90.3Labrie F,Cusan L,Gomez JL et al.Screening decreases prostate cancer mortality:11-year follow-up on the1988Quebec prospective randomized controlled trial.Prostate2004;59:311–18.4Andriole GL,Crawford ED,Grubb RL III et al.Prostate cancer screening in the randomized prostate,lung,colorectal,and ovarian cancer screening trial: mortality results after13years of follow-up.J.Natl.Cancer Inst.2012;104: 125–32.bs_bs_bannerInternational Journal of Urology(2013)doi:10.1111/iju.12162©2013The Japanese Urological Association1
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