Active treatment in low-risk prostate cancer: a population-based study.

Background: Active surveillance instead of active treatment (at) is preferred for patients with low-risk prostate cancer (lr-pca), but practice varies widely. We conducted a population-based study to assess the proportion of patients who underwent at between January 2011 and December 2014, and to evaluate factors associated with at. Methods: The provincial cancer registry was linked to administrative health datasets to identify patients with lr-pca and to acquire demographic, tumour, and treatment data. The primary outcome was receipt of at during the first 12 months after diagnosis, defined as any receipt of external-beam radiotherapy, brachytherapy, radical prostatectomy, cryotherapy, or androgen deprivation. Univariate and multivariate logistic regression were used to analyze the correlation between patient and tumour factors and at. Results: Of 1565 patients with lr-pca, 554 (35.4%) underwent at within 12 months of diagnosis. Radical prostatectomy was the most common treatment (58%), followed by brachytherapy (29.6%). Younger age [odds ratio (or) 0.92; 95% confidence interval (ci): 0.91 to 0.94], lower score (≥3) on the Charlson comorbidity index (OR: 0.36; 95% ci: 0.19 to 0.68), T2 stage (or: 3.05; 95% ci: 2.03 to 4.58), higher prostate-specific antigen (psa) at diagnosis (or: 1.13; 95% ci: 1.06 to 1.21), radiation oncologist consultation (or: 3.35; 95% ci: 2.55 to 4.39), and earlier diagnosis year (2012 or: 0.46; 95% ci: 0.34 to 0.63; 2013 or: 0.45; 95% ci: 0.32 to 0.63; 2014 or: 0.33; 95% ci: 0.23 to 0.47) were associated with a higher probability of at. Conclusions: This contemporary population-based study demonstrates that approximately one third of patients with lr-pca undergo at. Patients of younger age, with less comorbidity, a higher tumour stage, higher psa, earlier year of diagnosis, and radiation oncologist consultation were more likely to undergo at. Further investigation is needed to identify strategies that could minimize overtreatment.