Treatment Outcomes of 125I Low-Dose-Rate Brachytherapy vs Radical Prostatectomy for Patients with Intermediate-Risk Prostate Cancer

Objective: To compare the efficacy of radical prostatectomy vs low-dose-rate brachytherapy for patients with intermediate-risk prostate cancer.Materials and methods: A retrospective analysis was performed on 361 intermediate-risk prostate cancer patients who underwent treatment from January 2010 and August 2019. 160 underwent radical prostatectomy and 201 underwent low-dose-rate brachytherapy using Iodine-125. Biochemical failure for radical prostatectomy was defined as prostate-specific antigen levels > 0.2 ng/ml, and for low-dose-rate brachytherapy as nadir PSA level + 2 ng/ml. The log-rank test compared biochemical relapse-free survival between the two modalities, and Cox regression identified factors associated with biochemical relapse-free survival.Results: Median follow-up was 54 months for radical prostatectomy and 69 months for low-dose-rate brachytherapy. The 5-and 8-year biochemical relapse-free survival rates were 70.2% and 63.1% in the radical prostatectomy group, and 83.2% and 68.9% in the low-dose-rate brachytherapy group, respectively, P=0.003. There were no significant differences in terms of clinical relapse-free survival, cancer-specific survival or overall survival between the two groups. Conclusion: Low-dose-rate brachytherapy is a reasonable treatment option for intermediate-risk prostate cancer patients, yielding improved biochemical relapse-free survival and equivalent rates of clinical relapse-free survival, cancer-specific survival and overall survival compared with radical prostatectomy.