PSA: Declining utilization of prostate brachytherapy

To analyze rates of brachytherapy use for prostate cancer over time and evaluate patient characteristics, demographics and factors predictive for its utilization.

Data was retrospectively analyzed from the National Cancer Database (NCDB) for patients with localized prostate cancer treated between 2010 and 2015. Patients were included if they had biopsy confirmed localized adenocarcinoma of the prostate, were treated with radiation as definitive local therapy, and were at least 18 years old. Utilization rates of external beam radiation (EBRT), brachytherapy (BT) and combination (EBRT + BT) were evaluated over time. Univariable (UVA) and backwards elimination multivariable (MVA) analysis were performed to determine characteristics predictive for brachytherapy use.

We analyzed 178,837 patients with localized adenocarcinoma of the prostate treated between 2010 and 2015 with radiation therapy. During this period, the use of EBRT increased from 67% to 78%, BT (both monotherapy and combination with EBRT) decreased from 33% to 22%, BT monotherapy decreased from 25% to 16% and EBRT + BT decreased from 8% to 6%. Age >70, government funded insurance or lack of insurance, intermediate or high-risk disease and treatment at an academic center were associated with significantly lower utilization of brachytherapy (all p <0.001), while higher median zip code income was associated with increased use (p = 0.02). On multivariable analysis patients who were younger, had private insurance, were lower NCCN risk category and treated in non-academic cancer centers, had a higher rate of brachytherapy utilization. Notably, on both UVA and MVA brachytherapy practice decreased with increasing year of diagnosis (OR 0.881, 95% CI 0.853-0.910, p <0.001).

Rates of brachytherapy utilization for the treatment of prostate cancer continue to decrease over time. Treatment at an academic center was associated with reduced likelihood of brachytherapy use. This has significant implications for the training of future radiation oncology residents/fellows and direct consequences for both our patients and healthcare expenditure.