{'fraction_non_alphanumeric': 0.047743966421825816, 'fraction_numerical': 0.0472193074501574, 'mean_word_length': 4.904024767801857, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 5, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Five-year follow-up of active surveillance for prostate cancer: A Canadian community-based urological experience.

INTRODUCTON
We assessed oncological outcomes of active surveillance (AS) using a community database and identified factors associated with disease reclassification on surveillance biopsy.


METHODS
A retrospective review was performed on 200 men on AS. Prostate-specific antigen (PSA) was measured every 3 to 6 months. Prostate biopsies were performed every 1 to 4 years, and at the individual physician's discretion. Disease reclassification was defined as clinical T1 to cT2 progression, or histologically as >2 cores positive, Gleason score >6, or >50% core involvement on surveillance biopsy. Multivariate Cox regression analysis evaluated factors associated with disease reclassification. Kaplan-Meier survival curves were plotted.


RESULTS
We assessed a heterogeneous cohort of 86 patients, with a median age 67.2 years, who received ≥1 surveillance biopsies. The median follow-up was 5.2 years. The median times to first and second surveillance biopsies were 730 and 763 days, respectively. Overall, 47% of patients were reclassified on surveillance biopsy after a median 2.1 years. Factors associated with disease reclassification were PSA density >0.20 (p < 0.0001, hazard ratio [HR] 4.55, 95% confidence interval [CI] 2.116-9.782) and ≥3 positive cores (p = 0.0152, HR 3.956, 95% CI 1.304-12.003) at diagnosis, and number of positive cores on surveillance biopsy. In total, 25 (29%) patients received delayed intervention, with a median time to intervention of 2.6 years. The median time on AS was 4.4 years, with an overall survival of 95% and prostate-specific survival of 100%.


CONCLUSIONS
Our community study supports AS to reduce over-treatment of prostate cancer. PSA density >0.20 and ≥3 cores positive are associated with disease reclassification on surveillance biopsy.