Active surveillance for prostate cancer: current evidence and contemporary state of practice

Abstract

Prostate cancer remains one of the most commonly diagnosed malignancies worldwide. Early diagnosis and curative treatment seem to improve survival in men with unfavourable-risk cancers, but significant concerns exist regarding the overdiagnosis and overtreatment of men with lower-risk cancers. To this end, active surveillance (AS) has emerged as a primary management strategy in men with favourable-risk disease, and contemporary data suggest that use of AS has increased worldwide. Although published surveillance cohorts differ by protocol, reported rates of metastatic disease and prostate-cancer-specific mortality are exceedingly low in the intermediate term (5-10 years). Such outcomes seem to be closely associated with programme-specific criteria for selection, monitoring, and intervention, suggesting that AS--like other management strategies--could be individualized based on the level of risk acceptable to patients in light of their personal preferences. Additional data are needed to better establish the risks associated with AS and to identify patient-specific characteristics that could modify prognosis.

Figure 1. Recent years have seen a surge in the use of AS for patients with low-risk (CAPRA 0–2) prostate cancer, from a low of 6.7% between 1990 and 2009 to 40.4% between 2010 and 2013

Conservative management is also being used for patients with intermediate-risk (CAPRA 3–5) disease in 7.6% of cases. Appropriate care delivery for high-risk prostate cancer (CAPRA 6–10) has also changed during this period, with a reduction in the inappropriate use of primary androgen deprivation therapy and an increase in radical prostatectomy (from 25.3% to 53.3% of high-risk cancers). AS, active surveillance; CAPRA, UCSF Cancer of the Prostate Risk Assessment Score; PADT, primary androgen deprivation therapy; RP, radical prostatectomy; RT, radiation therapy; WW, watchful waiting. Figure courtesy of Dr Matt Cooperberg and based on data from recent CaPSURE update10. Permission obtained from Nature Publishing Group © Murphy, D. G. & Loeb, S. Nat. Rev. Urol. 12, 604–605 (2015).

Figure 2. Prostate cancer is heterogeneous in nature, with a spectrum of disease ranging from indolent to highly lethal

Accordingly, options for management range from conservative approaches such as watchful waiting, to a more aggressive approach with immediate definitive treatment. Active surveillance is an accepted management strategy for favourable-risk cancers. Approaches to active surveillance vary from non-intensive in men with indolent-appearing cancers who wish to minimize the morbidity of monitoring and potential treatment to a more intensive approach in others who wish to minimize the risk of unfavourable-risk cancer remaining undetected.