Editorial: Re‐thinking active surveillance for the multiparametric magnetic resonance imaging era

The last decade has seen a dramatic change in the management of low‐risk prostate cancer. Active surveillance (AS) has moved from a controversial management strategy to the preferred option for men with low‐risk disease. Despite widespread acceptance, there remain aspects of the pathway that men find difficult to accept, including the need for numerous repeat surveillance biopsies. In this issue of the BJUI, Gallagher et al. [1] report the outcomes of an AS programme using selective repeat biopsy based on multiparametric MRI (mpMRI) and PSA dynamics. The authors address the important issue of whether mpMRI can be used to safely avoid repeat biopsies in AS protocols.

The evidence for repeat biopsies in AS is based on studies from the pre‐MRI era, where up to 30% of men were upgraded on repeat systematic TRUS biopsy [2]. It has been established that TRUS biopsy is a highly unreliable test and misses a substantial proportion of clinically significant disease. The current approach requiring the repeated application of an unreliable test will not improve the systematic error inherent to the test. It is clear that the pathway needs to be updated for the mpMRI era, and the cohort of men in Gallagher et al. [1] provides valuable real‐life clinical data of an mpMRI‐based AS programme with a unique 4‐year follow‐up period.

The results are encouraging, with upgrading occurring in only 1.8% of men with a prior negative MRI. With follow‐up, progression to radical treatment was 12.8%, which is consistent with the established diagnostic performance of mpMRI. The authors seek further improvements by investigating if PSA dynamics can identify men with a negative MRI at risk of progression. They find that PSA velocity is strongly associated with subsequent progression (AUC 0.95, P < 0.001) and conclude that men on AS with low‐risk disease can safely avoid biopsy in favour of MRI, PSA monitoring and selective re‐biopsy. This study [1] supports a growing body of evidence that mpMRI may be adopted as the primary surveillance tool for men on AS. The finding regarding PSA velocity should be interpreted carefully as it contrasts with previous studies, which found that PSA dynamics have a limited role as independent predictors of disease progressions in AS [3]. A non‐invasive alternative to biopsy would be a valuable addition to AS and improve its acceptability as a management option. The burden of repeat surveillance biopsies for men on AS should not be underestimated. Indeed, in the present study ~30% of men declined biopsy in favour of continued mpMRI surveillance. The question is can we adapt our current standard AS approach for the mpMRI era? There are still many challenges and many unanswered questions. The cost‐effectiveness of mpMRI surveillance programmes needs to be established and the lack of MRI capacity remains a significant obstacle in introducing mpMRI pathways. The optimal imaging interval and the natural history of mpMRI lesions are just a few of the questions that need further research. These are exciting times to be a researcher in this field and there is much work to do as we start to build the new evidence‐base covering all the questions required for the mpMRI era.

References

1. Gallagher KM, Christopher E, Cameron AJ et al. Four‐year outcomes from a multiparametric magnetic resonance imaging (MRI)‐based active surveillance programme: PSA dynamics and serial MRI scans allow omission of protocol biopsies. BJU Int 2019; 123: 429–38.
2. Dall’Era MA, Albertsen PC, Bangma C et al. Active surveillance for prostate cancer: a systematic review of the literature. Eur Urol 2012; 62:976–83
3. Loblaw A, Zhang L, Lam A et al. Comparing prostate specific antigen triggers for intervention in men with stable prostate cancer on active surveillance. J Urol 2010; 184: 1942–6