Abstract
Many men diagnosed with localized prostate cancer can postpone definitive treatment without raising their risk of metastasis or death from disease. Active surveillance (AS) is a method of monitoring select men, with the option of switching to active treatment upon signs of progression, thereby avoiding the well-known side-effects of surgery and radiotherapy. This review analyzes the data from long-running AS cohorts to determine the safety and efficacy of AS. We conducted a narrative review of recently published data, including 14 articles from 13 AS cohorts. The cohorts used varying inclusion criteria, with reported differences in clinical T stage and Gleason Score (Grade Group), among other features. Some studies (n=5) limited their cohorts to low-risk patients, while others (n=8) also included intermediate-risk patients. The heterogeneity of the cohorts produced mixed results, with the risk of prostate cancer metastasis ranging from 0.1-1.0% at 10 years and the risk of prostate cancer mortality ranging from 0-1.9% at 10 years. However, the majority of studies reported risks of less than 0.5% at 10 years for both metastasis and death. For most cohorts, half of men remained untreated for 5-10 years, with estimates ranging from 37% receiving active treatment in the Toronto cohort to 73% in the Prostate Cancer Research International AS (PRIAS) study. Current data do not support the use of negative magnetic resonance imaging (MRI) to avoid scheduled biopsy. Taken together, the data collected from these AS cohorts suggests that AS is a safe approach for men with low-grade prostate cancer and some men with intermediate risk disease. AS should be more broadly implemented for eligible patients to avoid the decreases in quality of life from undergoing active treatment. Studies expanding the inclusion criteria and further defining a subset of men with favorable intermediate-risk prostate cancer who might safely benefit from AS are needed to assess the long-term outcomes of using AS in intermediate-risk groups.