Time Course and Accumulated Risk of Severe Urinary Adverse Events After High- Versus Low-Dose-Rate Prostate Brachytherapy With or Without External Beam Radiation Therapy

Toxicity differences were observed between LDR and HDR, but the differences did not meet statistical significance. However, combination radiation therapy (either HDR plus EBRT or LDR plus EBRT) increases the risk of severe UAEs compared with HDR alone or LDR alone. The highest increased risk of urinary toxicity occurs within the 2 years after therapy and then declines to an approximately 1% increase in incidence per year.