An assessment of Prostate Cancer Research International: Active Surveillance (PRIAS) criteria for active surveillance of clinically low-risk prostate cancer patients.

Introduction: Active surveillance is a strategy to delay or prevent treatment of indolent prostate cancer. The Prostate Cancer Research International: Active Surveillance (PRIAS) criteria were developed to select patients for prostate cancer active surveillance. The objective of this study was to compare pathological findings from PRIAS-eligible and PRIAS-ineligible clinically low-risk prostate cancer patients.

Methods: A D'Amico low-risk cohort of 1512 radical prostatectomy patients treated at The Ottawa Hospital or Memorial Sloan Kettering Cancer Centre between January 1995 and December 2007 was reviewed. Pathological outcomes (pT3 tumours, Gleason sum ≥7, lymph node metastases, or a composite) and clinical outcomes (prostate-specific antigen [PSA] recurrence, secondary cancer treatments, and death) were compared between PRIAS-eligible and PRIAS-ineligible cohorts.

Results: The PRIAS-eligible cohort (n=945) was less likely to have Gleason score ≥7 (odds ratio [OR] 0.61; 95% confidence interval [CI] 0.49-0.75), pT3 (OR 0.41; 95% CI 0.31-0.55), nodal metastases (OR 0.37; 95% CI 0.10-1.31), or any adverse feature (OR 0.56; 95% CI 0.45-0.69) compared to the PRIAS-ineligible cohort. The probability of any adverse pathology in the PRIAS-eligible cohort was 41% vs. 56% in the PRIAS-ineligible cohort. At median follow-up of 3.7 years, 72 (4.8%) patients had a PSA recurrence, 24 (1.6%) received pelvic radiation, and 13 (0.9%) received androgen deprivation. No difference was detected for recurrence-free and overall survival between groups (recurrence hazard ratio [HR] 0.71; 95% CI 0.46-1.09 and survival HR 0.72; 95% CI 0.36-1.47).

Conclusions: Low-risk prostate cancer patients who met PRIAS eligibility criteria are less likely to have higher-risk cancer compared to those who did not meet at least one of these criteria.