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Purpose: Low-dose-rate (LDR) brachytherapy and stereotactic body radiation therapy (SBRT) have both shown acceptable outcomes in the treatment of low- and intermediate-risk prostate cancer. Minimal data have been published directly comparing rates of biochemical control and toxicity with these 2 modalities. We hypothesize that LDR and SBRT will provide similar rates of biochemical control.Methods and Materials: All low- and intermediate-risk patients with prostate cancer treated definitively with SBRT or LDR between 2010 and 2018 were captured. Phoenix definition was used for biochemical failure. Independent t tests were used to compare baseline characteristics, and repeated measure analysis of variance test was used to compare American Urologic Association (AUA) and the Expanded Prostate Cancer Index Composite (EPIC) scores between treatment arms over time. Biochemical control was estimated using the Kaplan-Meier method. Differences in acute and late toxicity were assessed via Pearson χ2.Results: In the study, 219 and 118 patients were treated with LDR and SBRT. Median follow-up was 4.3 years (interquartile range, 3.1-6.1). All patients treated with LDR received 125.0 Gy in a single fraction. SBRT consisted of 42.5 Gy in 5 fractions. Five-year biochemical control for LDR versus SBRT was 91.6% versus 97.6% (P = .108). LDR patients had a larger increase in mean AUA scores at 1 month (17.2 vs 10.3, P < .001) and 3 months posttreatment (14.0 vs 9.7, P < .001), and in mean EPIC scores at 1 month (15.7 vs 13.8, P < .001). There was no significant difference between LDR and SBRT in late grade 3 genitourinary toxicity (0.9% vs 2.5%, P = .238); however, LDR had lower rates of late grade 3 gastrointestinal toxicity (0.0% vs 2.5%, P = .018).Conclusions: Our data show similar biochemical control and genitourinary toxicity rates at 5 years for both SBRT and LDR, with slightly higher gastrointestinal toxicity with SBRT and higher AUA and EPIC scores with LDR. [ABSTRACT FROM AUTHOR]

Purpose: Black men in the United States suffer significantly higher incidence of and mortality from prostate cancer (PCa) than non-Black men. The cause of this disparity is multifactorial, though inequitable access to curative radiation modalities, including low-dose-rate (LDR) brachytherapy, may contribute. Despite this, there are few analyses evaluating the potential of different radiation therapies to mitigate outcome disparities. Therefore, we examined the clinical outcomes of Black and non-Black patients treated with definitive LDR brachytherapy for prostate cancer.Methods: Data were collected for all patients treated with definitive LDR brachytherapy between 2005 and 2018 on a retrospective IRB-approved protocol. Pearson Chi-Squared analysis was used to assess demographic and cancer differences between Black and non-Black cohorts. Freedom from biochemical failure (FFBF) was calculated using Kaplan-Meier analysis. Univariate and multivariate analyses were used to identify factors predictive of biochemical failure.Results: One hundred and sixty-seven patients were included in the analysis (Black: n=81 [48.5%]) with a median follow-up of 88.4 months. Black patients were from lower income communities (P <0.01), had greater social vulnerability (P <0.01), and had a longer interval between diagnosis and treatment (P = 0.011). Overall cumulative FFBF was 92.3% (95% CI: 87.8% - 96.8%) at 5 years and 87.7% (95% CI: 82.0% - 93.4%) at 7 years. There was no significant difference in FFBF in Black and non-Black patients (P = 0.114) and Black race was not independently predictive of failure (HR 1.51 [95% CI: 0.56 - 4.01]; P = 0.42). Overall survival was comparable between racial groups (P = 0.972). Only nadir PSA was significantly associated with biochemical failure on MVA (HR = 3.57 [95% CI: 02.44 - 5.22]; P <0.001).Conclusions: Black men treated with LDR brachytherapy achieved similar FFBF to their non-Black counterparts despite poorer socioeconomic status. This suggests that PCa treatment with brachytherapy may eliminate some disparities clinical outcomes. [ABSTRACT FROM AUTHOR]