Interaction of MRI and active surveillance in prostate cancer: Time to re-evaluate the active surveillance inclusion criteria

Abstract

Currently available data from long-running single- and multi-center active surveillance (AS) studies show that AS has excellent cancer-specific survival rates. For AS to be effective the 'right' patients should be selected for which up until 5-to-10 years ago systematic prostate biopsies were used. Because the systematic prostate strategy relies on sampling efficiency for the detection of prostate cancer (PCa), it is subject to sampling error. Due to this sampling error, many of the Gleason 3+3 PCas that were included on AS in the early days and were classified as low-risk, may in fact have had a higher Gleason score. Subsequently, AS-criteria were more strict to overcome or limit the number of men missing the potential window of curability in case their tumor would be reclassified. Five to ten years ago the prostate biopsy landscape changed drastically by the addition of magnetic resonance imaging (MRI) into the diagnostic PCa-care pathway, which has by now trickled down into the EAU guidelines. At the moment, the EAU guidelines recommend performing a (multi-parametric) MRI before prostate biopsy and combine systematic and targeted prostate biopsy when the MRI is positive (i.e. PIRADS ≥3). So because of the introduction of the MRI into the diagnostic PCa-care pathway, literature is showing that more Gleason 3+4 PCas are being diagnosed. But can it not be that the inclusion of MRI into the diagnostic PCa-care pathway causes risk inflation, resulting in men earlier eligible for AS, now being labelled ineligible for AS? Would it not be possible to include these current Gleason 3+4 PCas on AS? The authors hypothesize that the improved accuracy that comes with the introduction of MRI into the diagnostic PCa-care pathway permits to widen both the AS-inclusion and follow-up criteria. Maintaining our inclusion criteria for AS from the systematic biopsy era will unnecessarily and undesirably expose patients to the increased risk of overtreatment. The evidence behind the addition of MRI-targeted biopsies to systematic biopsies calls upon the re-evaluation of the AS inclusion criteria and research from one-size-fits-all protocols used so far, into the direction of more dynamic and individual risk-based AS-approaches.