Results from a prospective clinical trial suggest a single, 19-Gray (Gy) high-dose–rate (HDR) of brachytherapy is a safe and effective option over longer courses of HDR therapy for patients with localized prostate cancer.1
Brachytherapy is a procedure in which surgical implants inserted within or near diseased tissue deliver curative radiation directly to the cancerous cells. The method limits radiation exposure to surrounding tissue, which is particularly important in prostate cancer as the prostate is surrounded by several critical structures.
In HDR brachytherapy, implants are removed whereas in low-dose–rate brachytherapy, implants are placed permanently in the body to slowly deposit radiation over a period of months.
HDR brachytherapy is usually administered in 4 to 9 sessions, requiring several invasive procedures. Here, results indicate a single HDR brachytherapy session of 19 Gy resulted in similar clinical outcomes as LDR brachytherapy.
In this prospective, non-randomized clinical trial, 58 patients with low-risk or intermediate-risk, nonmetastatic prostate cancer received a single, 19-Gy fraction of HDR brachytherapy. Median follow-up was 2.9 years. Median age was 63 years, and 91% of patients presented with stage T1 disease.
At follow-up, control rates for cancer were favorable, and the toxicity profile was highly favorable. Estimated 3-year cumulative biochemical control rate was 93%, with 3 patients experiencing recurrence or disease progression.
Seven patients (12.1%) experienced grade 2 urinary side effects within 6 months of HDR brachytherapy. No patients experienced short-term grade 3 or greater urinary toxicity or grade 2 or greater gastrointestinal toxicity.
Long-term side effects were similarly highly favorable: 6 patients (10.3%) experienced chronic grade 2 urinary toxicity. One patient (1.7%) experienced grade 3 gastrointestinal toxicity that resolved.
“This study illustrates that a potentially curative dose of radiation may be delivered safely to the prostate entirely in a single administration,” explained Daniel J. Krauss, MD, a radiation oncologist at Oakland University’s William Beaumont School of Medicine in Royal Oak, Michigan.
“Giving the entire dose in a single treatment theoretically could have had a greater negative impact on the normal tissues in close proximity to the prostate, meaning the bladder, urethra and rectum, but this was not found to be the case. Toxicity rates were extremely low, with essentially no major complications encountered in this initial group of 58 patients.”
Additional follow-up to compare long-term control of disease with standard therapy is needed.
1. Krauss DJ, Ye H, Martinez AA, et al. Favorable preliminary outcomes for men with low- and intermediate-risk prostate cancer treated with 19-Gy single-fraction high-dose-rate brachytherapy. Int J Radiat Oncol Biol Phys. 2017;97(1):98-106.