Platinum Priority Reply from Authors re: Michael Baum. Screening for Prostate Cancer: Can We Learn from the Mistakes of the Breast Screening Experience? Eur Urol. In press. http://dx.doi.org/10.1016/j.eururo.2013.05.053 Screening for Prostate Cancer: We Have Learned and Are Still Learning Monique J. Roobol a, *, Ries Kranse b , Chris H. Bangma a , Suzie J. Otto c , Theo H. van der Kwast d , Leonard P. Bokhorst a , Harry J. de Koning c , Fritz H. Schro ¨der a a Erasmus University Medical Center, Department of Urology, Rotterdam, The Netherlands; b Comprehensive Cancer Center, Rotterdam, The Netherlands; c Erasmus University Medical Center, Department of Public Health, Rotter- dam, The Netherlands; d Erasmus University Medical Center, Department of Pathology, Rotterdam, The Netherlands In the days when we had the pleasure of being young undergraduates, we learned one important thing: The most important question in medicine is not what the doctor wants or thinks is best for the patient but rather what the patient wants or thinks is best for the patient. The duty of the doctor is to guide the patient through the best available evidence so the patient can make a choice about what is best. That said, we greatly appreciate the thoughtful words of Dr. Baum on the issue of prostate cancer (PCa) screening [1]. The goal of cancer screening is, as is correctly stated, not to catch the disease early. On the contrary, detecting the disease early and hence being a cancer patient for a longer period is one of the most important issues in evaluating the harms and benefits of cancer screening. The European Randomized Study of Screening for Prostate Cancer (ERSPC; http:// www.erspc-media.org/erspc-background/) has PCa mortali- ty as a main end point. However, length of life (LoL) and, perhaps even more important, quality of life (QoL) are also end points extensively studied within ERSPC [2]. Starting with PCa mortality, Baum refers to our first paper published in 2009 in the New England Journal of Medicine [3]. Looking at the number needed to invite (NNI; 1410), one could conclude that it is not impressive enough to consider PCa screening as a way of increasing LoL. There is, however, more than meets the eye, and more published data from the ERSPC are available. The results published in 2009 reported on PCa mortality at 9 yr of follow-up. At that time, only 15% of the study population of both arms had died. At the 11-yr follow-up report [4], the NNI decreased to 936, with 20% of the study population having died. In the current report on the Rotterdam section, with 13 yr of follow-up (and 25% of men having died), the NNI decreased to 392 [5]. This shows that the NNI is heavily dependent on the proportion of participants that reached the end point. The true NNI can be given only if all participants pass away. For now, to be able to make assumptions about the true effect of screening on a population-based level, we have to extrapolate the results. In this respect, we refer to a publication on QoL aspects of PCa screening [6]. On the basis of ERSPC follow-up data and the use of microsimulation screening analysis, effects of screening were calculated per 1000 men of all ages who were followed up for their entire life span. With annual screening of men between the ages of 55–69 yr, nine PCa deaths would be avoided (ie, instead of 31 PCa deaths, 22 men would die of their disease). A total of 73 life-years would be gained (on average, 8.4 yr per PCa death avoided). In addition, when looking over a total life span and not limited by, for example, only 11 yr of available follow-up, 98 men would need to be screened and five cancers would need to be detected or treated to prevent one PCa death. Does this increase LoL? When extrapolating these numbers to the Dutch population, a relatively small country with 8.1 million men, we could avoid the PCa deaths of 72 900 men (8.1 million per 1000 Â 9 PCa deaths avoided) and prolong their lives, on average, 8.4 yr. Are these figures enough to recommend PCa screening? That depends on what is most important to policymakers and individual men. PCa screening does cause a risk of overdiagnosis of approximately 50% [7] and of overtreatment, and both are estimated to decrease the gain in life-years by 23% [6]. From this perspective, we must note that the simple comparison described by Baum [1]—771 deaths in men diagnosed with PCa in the screening arm compared with 483 deaths among PCa patients in the control arm, without taking into account the mentioned 1.9-fold higher incidence of PCa in E U R O P E A N U R O L O G Y X X X ( 2 0 1 3 ) X X X – X X X ava ilable at www.sciencedirect.com journa l homepage: www.europea nurology.com DOIs of original articles: http://dx.doi.org/10.1016/j.eururo.2013.05.030, http://dx.doi.org/10.1016/j.eururo.2013.05.053. * Corresponding author. Erasmus University Medical Center, Department of Urology, PO Box 2014, 3000 CA Rotterdam, The Netherlands. E-mail address: m.roobol@erasmusmc.nl (M.J. Roobol). EURURO-5180; No. of Pages 3 Please cite this article in press as: Roobol MJ, et al. Reply from Authors re: Michael Baum. Screening for Prostate Cancer: Can We Learn from the Mistakes of the Breast Screening Experience? Eur Urol. In press. http://dx.doi.org/10.1016/j.eururo.2013.05.053 Eur Urol (2013), http://dx.doi.org/10.1016/j.eururo.2013.06.033 0302-2838/$ – see back matter # 2013 European Association of Urology. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.eururo.2013.06.033