Characteristics of patients managed with active surveillance versus treatment for prostate cancer within a large nationwide health system.

e17129 Background: Active surveillance (AS) is broadly endorsed as preferred management for low-grade prostate cancer and has been increasingly adopted within the VA Health Care System (VAHCS). This study analyzes the characteristics of VAHCS patients managed with AS rather than immediate treatment, as well as those that receive confirmatory biopsy (CBx) within 24 months of diagnostic biopsy (DBx), in order to evaluate the factors that direct physicians to utilize AS for low-grade prostate cancer. Methods: A retrospective cohort was identified using patients listed in the VA Informatics and Computing Infrastructure (VINCI) Prostate Data Core. Using natural language processing (NLP), the cohort was limited to patients with a DBx between 2005 and 2024 indicating Gleason Grade Group (GG) 1 prostate cancer or GG 2 prostate cancer with < 50% positive cores at DBx. Patients were stratified by whether they received treatment (radiation, prostatectomy, and/or orchiectomy/ADT) during the first 15 months or remained on AS or watchful waiting (WW). Patients with CBx prior to treatment or at least one PSA > 1 ng/mL were classified as managed with AS/WW. Patients were censored due to death, progression to metastatic status, no recorded PSA labs within 15 months, or a reported PSA value < 1 ng/mL. Hierarchical mixed-effects logistic models were used to analyze AS usage and CBx administration within 24 months of DBx with VA facility as a random effect. Results: There were 173,725 patients with a positive biopsy for prostate cancer between 2005 and 2024. Of those diagnosed with GG 1 prostate cancer or GG 2 with < 50% positive cores, 40,341 patients (49.7%) were managed with AS/WW while 40,872 patients (50.3%) received treatment during the first 15 months after diagnosis. Since 2015, the proportion managed with AS was 64%. Black or African American patients were less likely to be managed by AS (OR: 0.84; 95% CI: 0.80-0.88; p < 0.001) or receive CBx within 24 months of DBx (OR: 0.84; 95% CI: 0.79-0.88; p < 0.001). AS management was also less likely among Hispanic or Latino patients (OR: 0.83, 95% CI: 0.74-0.93; p < 0.001), while older patients were more likely to be managed by AS (OR: 1.26 per decade, 95% CI: 1.23-1.30; p < 0.001). Patients in zip codes with a higher area deprivation index (ADI) also had lower AS utilization (OR: 0.96 per quartile; 95% CI: 0.94-0.98; p < 0.001) and CBx receipt (OR: 0.96; 95% CI: 0.93-0.98; p < 0.001). Results are robust for age, race, and ethnicity when limiting the cohort to diagnoses between 2015 – 2024 and stratification by GG. Conclusions: Prostate cancer care in the VAHCS reflects the best uptake of AS/WW for favorable risk disease in the country. By analyzing the characteristics of patients managed by AS and receiving quality AS through CBx receipt, further efforts can be made to adapt these management practices for low-grade prostate cancer.