Salvage brachytherapy for locally recurrent prostate cancer after single-fraction 19 Gy high-dose-rate brachytherapy: toxicity, prostate-specific antigen kinetics, and cancer control

Abstract

Purpose To evaluate toxicity, prostate-specific antigen (PSA) kinetics, and cancer control of high-dose-rate brachytherapy (HDR-BT) as a salvage modality for men with locally recurrent prostate cancer, after primary HDR-BT failure. Material and methods Twelve patients with biochemical failure and a local relapse after 19 Gy single-fraction high-dose-rate brachytherapy (HDR-BT 19 Gy) were salvaged using two HDR-BT fractions. Salvage treatment consisted of two HDR-BT applications, one week apart, delivering 12 Gy to the prostate per application (HDR-BT 12 × 2). Results Median age and initial PSA prior to rescue treatment were 74 years (range, 65-80) and 5.29 ng/ml (range, 2.37-16.40), respectively. Forty-two percent had a low-risk and 58% presented with intermediate-risk prostate cancer. Median follow-up period was 26 months (range, 10-42). Median time to PSA nadir was 12 months, with a median value of 0.21 ng/ml. Most of the patients (11 of 12) achieved a PSA decline ≥ 90%. Acute grade 2 genitourinary (GU) toxicity occurred in 4 patients (33.3%) and none presented with acute gastrointestinal (GI) toxicity. Two patients (16.7%) suffered from late GU grade 2 toxicity. No grade 3 toxicity were recorded. To date, 2 patients (16.7%) have experienced biochemical failure after salvage treatment. Conclusions Salvage HDR-BT 12 × 2 is a feasible and well-tolerated treatment, with acceptable toxicity rates for men with locally recurrent prostate cancer, who failed after HDR-BT with 19 Gy. Moreover, PSA kinetics and cancer control after salvage treatment suggest that this strategy might be efficacious in this clinical setting.

The potential of low-dose-rate brachytherapy with iodine-125 in the treatment of local recurrences of prostate cancer after primary high-dose-rate monotherapy

“…There was no gastrointestinal toxicity. Two biochemical recurrences were reported during a median follow-up of 26 months [7].…”

“…It is possible to use salvage HDR-BT, LDR-BT, or salvage prostatectomy (SRP), previously described in reviews concerning this topic [5,6]. On the other hand, there are no articles concerning salvage prostatectomy for locally recurrent prostate cancer after monotherapy with HDR-BT, and a report about secondary HDR-BT contains only results of patients treated with an insufficient dose of 1 × 19 Gy [7].…”

“…Outcomes of salvage treatment after primary HDR-BT monotherapy were presented by Maryata et al in 2021. Twelve patients treated previously with 1 × 19 Gy scheme were presented [7]. Patients were enrolled in phase II prospective trial, and had histopathologically confirmed prostate cancer recurrence [27].…”