Patient and Context Factors in the Adoption of Active Surveillance for Low-Risk Prostate Cancer.

Importance: Although active surveillance for patients with low-risk prostate cancer (LRPC) has been recommended for years, its adoption at the population level is often limited. Objective: To make active surveillance available for patients with LRPC using a research framework and to compare patient characteristics and clinical outcomes between those who receive active surveillance vs radical treatments at diagnosis. Design, Setting, and Participants: This population-based, prospective cohort study was designed by a large multidisciplinary group of specialists and patients' representatives. The study was conducted within all 18 urology centers and 7 radiation oncology centers in the Piemonte and Valle d'Aosta Regional Oncology Network in Northwest Italy (approximate population, 4.5 million). Participants included patients with a new diagnosis of LRPC from June 2015 to December 2021. Data were analyzed from January to May 2023. Exposure: At diagnosis, all patients were informed of the available treatment options by the urologist and received an information leaflet describing the benefits and risks of active surveillance compared with active treatments, either radical prostatectomy (RP) or radiation treatment (RT). Patients choosing active surveillance were actively monitored with regular prostate-specific antigen testing, clinical examinations, and a rebiopsy at 12 months. Main Outcomes and Measures: Outcomes of interest were proportion of patients choosing active surveillance or radical treatments, overall survival, and, for patients in active surveillance, treatment-free survival. Comparisons were analyzed with multivariable logistic or Cox models, considering centers as clusters. Results: A total of 852 male patients (median [IQR] age, 70 [64-74] years) were included, and 706 patients (82.9%) chose active surveillance, with an increasing trend over time; 109 patients (12.8%) chose RP, and 37 patients (4.3%) chose RT. Median (IQR) follow-up was 57 (41-76) months. Worse prostate cancer prognostic factors were negatively associated with choosing active surveillance (eg, stage T2a vs T1c: odds ratio [OR], 0.51; 95% CI, 0.28-0.93), while patients who were older (eg, age ≥75 vs <65 years: OR, 4.27; 95% CI, 1.98-9.22), had higher comorbidity (Charlson Comorbidity Index ≥2 vs 0: OR, 1.98; 95% CI, 1.02-3.85), underwent an independent revision of the first prostate biopsy (OR, 2.35; 95% CI, 1.26-4.38) or underwent a multidisciplinary assessment (OR, 2.65; 95% CI, 1.38-5.11) were more likely to choose active surveillance vs active treatment. After adjustment, center at which a patient was treated continued to be an important factor in the choice of treatment (intraclass correlation coefficient, 18.6%). No differences were detected in overall survival between active treatment and active surveillance. Treatment-free survival in the active surveillance cohort was 59.0% (95% CI, 54.8%-62.9%) at 24 months, 54.5% (95% CI, 50.2%-58.6%) at 36 months, and 47.0% (95% CI, 42.2%-51.7%) at 48 months. Conclusions and Relevance: In this population-based cohort study of patients with LRPC, a research framework at system level as well as favorable prognostic factors, a multidisciplinary approach, and an independent review of the first prostate biopsy at patient-level were positively associated with high uptake of active surveillance, a practice largely underused before this study.