European Urology

Postma R, de Vries SH, Roobol MJ, Wildhagen MF, Schröder FH, van der Kwast TH
Cancer 2005;103:708–16
Expert's summary:
This study evaluated the clinicopathologic features of patients with focal carcinoma (≤3.0 mm in only one core of sextant biopsies, lacking Gleason patterns 4 and 5). The patients underwent radical prostatectomy (RP, n = 103) or were monitored regularly (the “wait and watch” method [WW], n = 108). RP specimens were categorized into minimal tumours (volume <0.5 ml, no Gleason patterns 4 and 5, organ confined, and negative surgical margins) or moderate-to-advanced tumours (volume ≥0.5 ml, Gleason pattern 4 or 5 detectable, extracapsular extension, or positive surgical margins). The median tumour volume in RP specimens was 0.13 ml, and in 78.6% of the cases it was <0.5 ml. In 3 specimens, no tumour was found. A prostate-specific antigen (PSA) density cutoff level of ≤0.1 ng/ml/cm³ predicted a tumour volume of <0.5 ml in 94% of cases. Because it was part of the European Randomized Screening Study for Prostate Cancer, the study also showed that the proportion of patients with focal prostate carcinoma increased significantly, from 16% during the first screening round to 29% during the second round, 4 years later. The median tumour volume in the first round (PSA ≥ 4) was 0.16 ml, and that in the second round (PSA ≥ 3) was 0.07 ml, but this difference did not reach statistical significance.
Expert's opinion:
The authors concluded that the WW policy with delayed curative intent may be recommended in patients 55–75 yr old who have focal carcinoma and a PSA density <0.1 ng/ml/cm³. Natural-history data from other cohorts have shown the indolent character of low-grade prostate cancer, with 15-year disease-specific survival rates of approximately 80% [1] and [2]. The follow-up time of the present study is still short, and the mortality in the RP and WW groups cannot be analyzed yet. A Scandinavian randomized study [3] showed better results for patients with RP, but most cancers were clinically detectable. Even then, because of a small absolute reduction in prostate cancer mortality, 19 patients needed to be treated to prevent one death at 10 years. Respective speculations for today's low-risk small tumours increase this number to 100 patients [4]. This is ethically unacceptable. It is impossible to stop prostate cancer screening, but if the PSA threshold is lowered from 4 to 3 or even lower, and 12 biopsies are routinely done, we are going to find a large number of insignificant cancers. Surgeons like to operate, but it is not meaningful to shoot mosquitoes with a cannon. Proper guidelines for screening and the WW policy are urgently needed.