Screening for prostate cancer. Key studies have only just started.

Editor—Whelan is correct in stating that “there is no turning the clock back” to the era of the management of prostate cancer before testing for prostate specific antigen was available.1 It is a pity, however, that he is so negative about the antigen, which has stimulated an enormous amount of research into prostate cancer since its discovery. Good evidence shows that prostate cancer is not always as indolent as suggested. The best available population based cohort study of conservative management shows that men with moderately differentiated tumours (three quarters of the tumours) lose 4-5 years of life and those with poorly differentiated tumours lose 6-8 years of life.2 In addition, Whelan himself admits that half of men dying of prostate cancer are under 75 and a considerable proportion are under 65. The description of prostate cancer as a “homely” disease does not square with the observations of most practitioners who look after patients dying of metastatic prostate cancer. We would all be delighted to base our actions on the results of randomised controlled trials, but we are dealing with new molecular technology and the key studies are only just under way.3 For the individual patient, the potentially false reassurance that prostate cancer is a non-progressive disease is not evidence based. An increasing body of evidence shows that tumours detected by measurement of prostate specific antigen, far from being unimportant well differentiated tumours, are predominantly moderately differentiated (Gleason score 5-7), which are being diagnosed at an earlier, and therefore curable, stage.4 In the absence of evidence from randomised controlled trials, general practitioners and urologists need to present the putative pros and cons of having the prostate specific antigen test, and the potential advantages and disadvantages of radical treatment, and allow informed patients to decide for themselves whether they wish to be investigated.