Salvage Magnetic Resonance Imaging–guided Transurethral Ultrasound Ablation for Localized Radiorecurrent Prostate Cancer: 12-Month Functional and Oncological Results

Abstract

Background Up to half of all men who undergo primary radiotherapy for localized prostate cancer (PCa) experience local recurrence. Objective To evaluate the safety and early functional and oncological outcomes of salvage magnetic resonance imaging–guided transurethral ultrasound ablation (sTULSA) for men with localized radiorecurrent PCa. Design, setting, and participants This prospective, single-center phase 1 study ( NCT03350529 ) enrolled men with biopsy-proven localized PCa recurrence after radiotherapy. Multiparametric magnetic resonance imaging (mpMRI) and 18 F prostate-specific membrane antigen-1007 ( 18 F PSMA-1007) positron emission tomography (PET)-computed tomography (CT) were used to confirm organ-confined disease localization. Patients underwent either whole-gland or partial sTULSA, depending on their individual tumor characteristics. Outcome measurements and statistical analysis Patients were followed at 3-mo intervals. Adverse events (AEs, Clavien-Dindo scale), functional status questionnaires (Expanded Prostate Cancer Index [EPIC]-26, International Prostate Symptom Score, International Index of Erectile Function-5), uroflowmetry, and prostate-specific antigen (PSA) were assessed at every visit. Disease control was assessed at 1 yr using mpMRI and 18 F-PSMA-1007 PET-CT, followed by prostate biopsies. Results and limitations Eleven patients (median age 69 yr, interquartile range [IQR] 68–74) underwent sTULSA (3 whole-gland, 8 partial sTULSA) and have completed 12-mo follow-up. Median PSA was 7.6 ng/ml (IQR 4.9–10) and the median time from initial PCa diagnosis to sTULSA was 11 yr (IQR 9.5–13). One grade 3 and three grade 2 AEs were reported, related to urinary retention and infection. Patients reported a modest degradation in functional status, most significantly a 20% decline in the EPIC-26 irritative/obstructive domain at 12 mo. A decline in maximum flow rate (24%) was also observed. At 1 yr, 10/11 patients were free of any PCa in the targeted ablation zone, with two out-of-field recurrences. Limitations include the nonrandomized design, limited sample size, and short-term oncological outcomes. Conclusions sTULSA appears to be safe and feasible for ablation of radiorecurrent PCa, offering encouraging preliminary oncological control. Patient summary We present safety and 1-yr functional and oncological outcomes of magnetic resonance imaging–guided transurethral ultrasound ablation (TULSA) as a salvage treatment for local prostate cancer recurrence after primary radiation. Salvage TULSA is safe and shows the ability to effectively ablate prostate cancer recurrence, with acceptable toxicity.

Magnetic Resonance Imaging-Guided Transurethral Ultrasound Ablation of Prostate Cancer: A Systematic Review

“…The following three indications for TULSA were identified: primary localized PCa (198 patients, 4 unique cohorts,), 8–14 salvage treatment for recurrent PCa (16 patients, 2 cohorts), 10 , 15 and palliation for locally advanced PCa (LAPC) (10 patients, 1 cohort) ( Table 1 ). 16 The LAPC cohort comprised men requiring palliative surgical treatment for urinary retention and gross hematuria.…”

“…Sixteen men received TULSA for recurrent PCa, between a prospective cohort of 11 men with radiorecurrent disease 15 and a retrospective cohort of 5 men with recurrence after high-intensity focused ultrasound (HIFU) (2), laser and HIFU (1), EBRT (1), and hyperthermia (1) ( Table 2 ). 10 At a median of 12- to 16-month follow-up, 2/16 (12%) men experienced BCR and 3/16 (19%) had a positive mpMRI.…”

“…Of the 4/16 (25%) men who had salvage treatment, 3 of these treatments were directed by out-of-field recurrence. 10 , 15 One of the out-of-field recurrences (plus an in-field failure that was managed expectantly) was seen only on per-protocol PSMA-PET. 15 Both men had negative mpMRI and no biochemical failure.…”

Magnetic resonance imaging‐guided transurethral ultrasound ablation for benign prostatic hyperplasia: 12‐month clinical outcomes of a phase I study

“…TULSA has primarily been investigated for the ablation of localised prostate cancer (PCa) [12,13], demonstrating good efficacy with low toxicity and an ability to treat large prostates up to 125 mL [13]. More recently, TULSA has been investigated for salvage treatment of radiorecurrent PCa [14] and palliative treatment of locally advanced PCa [15]. Results from a retrospective subgroup analysis of nine men with localised PCa and concurrent symptomatic BPO who underwent TULSA showed encouraging results, reporting an 89% improvement in IPSS and quality of life (QoL), and preservation of antegrade ejaculations in eight out of nine patients at 12 months after TULSA [16], although the few patients and retrospective study design makes it difficult to draw any firm conclusions.…”

Minimally invasive magnetic resonance image-guided prostate interventions

“…None of the patients had a rectal injury, 96% returned to baseline urinary continence and 75% of potent males maintained or returned to erections sufficient for penetration. Recently, Attinen et al 37 showed promising early-stage oncological control and low toxicity in patients undergoing TULSA as salvage treatment for local recurrence after primary radiation. 90% of the patients were free of disease in the targeted ablation area one year after treatment.…”