Evaluating the Outcomes of Active Surveillance in Grade Group 2 Prostate Cancer: Prospective Results from the Canary PASS Cohort.

PURPOSE: Active surveillance (AS) for grade group (GG) 2 patients is not yet well defined. We sought to compare clinical outcomes of men with GG1 and GG2 prostate cancer undergoing AS in a large prospective North American cohort. MATERIALS AND METHODS: Participants were prospectively enrolled in an AS study with protocol-directed followup at 10 centers in the U.S. and Canada. We evaluated time from diagnosis to biopsy grade reclassification and time to treatment. In men treated after initial surveillance, adverse pathology and recurrence were also analyzed. RESULTS: At diagnosis, 154 (9%) had GG2 and 1,574 (91%) had GG1. Five-year reclassification rates were similar between GG2 and GG1 (30% vs 37%, p=0.11). However, more patients with GG2 were treated at 5 years (58% vs 34%, p <0.001) and GG at diagnosis was associated with time to treatment (HR=1.41; p=0.01). Treatment rates were similar in patients who reclassified during AS, but in patients who did not reclassify, those diagnosed with GG2 underwent definitive treatment more often than GG1 (5-year treatment rates 52% and 12%, p <0.0001). In participants who underwent radical prostatectomy after initial surveillance, the adjusted risk of adverse pathology was similar (HR=1.26; p=0.4). Biochemical recurrence within 3 years of treatment for GG2 and GG1 patients was 6% for both groups. CONCLUSIONS: In patients on AS, the rate of definitive treatment is higher after an initial diagnosis of GG2 than GG1. Adverse pathology after radical prostatectomy and short-term biochemical recurrence after definitive treatment were similar between GG2 and GG1.

Effect of Diagnostic Biopsy Practice Location on Grade/Volume Reclassification in Active Surveillance for Prostate Cancer: A Multicenter Analysis from the Canary PASS Cohort.

INTRODUCTION: We analyzed the Canary Prostate Cancer Active Surveillance (PASS) cohort to determine if patients who had diagnostic biopsy at an off-site practice were at higher risk of reclassification than those having their diagnostic biopsy at a PASS site. METHODS: Participants were prospectively enrolled at 10 academic institutions. We included patients with Gleason score 6 at diagnostic biopsy, <34% positive cores and a first surveillance biopsy in a PASS site <2 years after diagnosis. We dichotomized our population based on diagnostic biopsy location (on-PASS site vs off-PASS site) and used multivariable logistic regression to evaluate association with reclassification at first surveillance biopsy after controlling for possible confounders. We used Fisher's exact test to compare rates of definitive prostate cancer treatment by diagnostic biopsy location. RESULTS: Out of 1,648 participants in PASS, 906 met the eligibility criteria and were analyzed. Of 519 men who had off-site diagnostic biopsy, 102 (20%) had grade/volume reclassification compared to 72 (19%) of 399 patients who had on-site diagnostic biopsy. After controlling for potential confounders, location of diagnostic biopsy was not significantly associated with grade/volume reclassification (OR 1.32, IQR 0.91-1.92; p=0.141). Participants with an off-site diagnostic biopsy were more likely to elect definitive treatment than participants with an on-site diagnostic biopsy (17%, IQR 14-20 vs 14%, IQR 10-17 within 1 year after first surveillance biopsy; p <0.01). CONCLUSIONS: In this evaluation of a large multicenter active surveillance cohort, diagnostic biopsy location was not associated with significant differences in grade/volume reclassification on confirmatory biopsy at academic institutions.