12-Month Outcomes of Salvage TULSA for Radio-Recurrent Prostate Cancer

Men diagnosed with radio-recurrent prostate cancer (PCa) often face significant challenges due to limited options for salvage therapies. MRI-guided transurethral ultrasound ablation (TULSA) has emerged as a promising treatment for localized PCa, demonstrating favorable clinical outcomes in various settings. This study presents the 12-month safety and oncological outcomes of salvage TULSA (sTULSA) specifically for men experiencing localized radio-recurrent PCa. Conducted as a prospective, single-center, phase 1-2 study (NCT03350529), the research included men with biopsy-proven localized PCa recurrence following primary radiation therapy. To ensure accurate diagnosis, multiparametric MRI (mpMRI) and 18-F prostate-specific membrane antigen (PSMA)-1007 PET-CT were utilized to confirm organ-confined disease. Following treatment, patients were monitored every three months for adverse events (AEs) classified according to the Clavien-Dindo system, quality-of-life (QoL) assessments, uroflowmetry, and prostate-specific antigen (PSA) levels. The primary endpoint for disease control was evaluated at the 12-month mark through mpMRI, PSMA PET-CT, and targeted prostate biopsy of the treatment area along with any suspicious areas noted during imaging. A total of 41 men received sTULSA, with 25 undergoing whole-gland ablation and 16 receiving focal ablation. One participant withdrew due to the frequent follow-up requirements three months post-treatment despite achieving undetectable PSA levels (<0.006 ng/ml). The median age of participants was 73 years (IQR 69-77), with a baseline PSA of 3.3 ng/ml (IQR 2.3-7) and an average interval of 11 years (IQR 8-13) between initial radiation therapy and sTULSA. Of the patients, 26 received fiducial markers. At the 12-month follow-up, AEs included two grade 3 events requiring intervention (urethral stricture and stent placement) and 17 grade 2 events such as urinary tract infections (UTIs), osteitis pubis, urinary retention, pyelonephritis, urosepsis, and hematuria. Remarkably, the median PSA at 12 months post-sTULSA was 0.19 ng/ml (IQR 0.07–0.57), with 13 patients achieving undetectable PSA levels (<0.1). Two patients were diagnosed with biochemical recurrence (PSA≥nadir+2) at the 12-month follow-up, correlating with extraprostatic disease on imaging. Imaging results indicated that 28 out of 31 men (90%) showed no visible cancer in the prostate, while four patients had seminal vesicle invasion. Biopsy outcomes revealed that 26 out of 30 patients (87%) were free of any PCa in the treatment region, although four patients had positive out-of-field biopsies. The 12-month clinical outcomes of sTULSA show remarkable oncological results with acceptable toxicity for treating localized radio-recurrent PCa.