ORLANDO, Fla.—Salvage brachytherapy may be an option for prostate cancer (PCa) patients who experienced recurrent cancer in the prostate bed following radical prostatectomy (RP), researchers from the Cleveland Clinic reported at the annual Genitourinary Cancers Symposium.
The case series included 12 patients with prostate bed nodules who received low-dose-rate brachytherapy with I-125 implants prescribed to 144 Gy. The median interval between RP and brachytherapy was eight years. The median PSA level prior to BT was 4.53 ng/mL. The median follow-up was 26.5 months.
At the time of analysis, 10 patients were evaluable for biochemical failure (defined as PSA nadir plus 2 ng/mL) and distant metastases. The one- and two-year rates of biochemical failure were 0% and 52%. Distant metastases developed in the pelvic lymph nodes of two patients, one at 17 months and the other at 55 months after brachytherapy. The researchers stated that the rates of biochemical failure and distant metastases found in their series are comparable to those of salvage external beam radiotherapy in this patient population.
At last follow-up, five patients had a negative PSA velocity and four had an increasing PSA velocity. PSA velocity could not be ascertained for three patients. To date, no gastrointestinal or urinary toxicities have been observed, even though some patients previously had salvage external beam radiotherapy. “We were able to re-irradiate an area without introducing any news toxicites,” said researcher Kristin Smith, who presented study findings.
Smith noted that salvage brachytherapy for locally recurrent cancer in the prostate bed following RP, which had not previously been studied, is a potential new treatment option.