43 - Robotic Assisted MRI-Guided Transurethral Ultrasound Ablation in Recurrent Prostate Cancer: A Retrospective Analysis

Purpose: Effective management of locally recurrent prostate cancer remains a clinical challenge. Transurethral ultrasound ablation (TULSA) uses MR image-guided prostate tissue ablation, which has the potential to achieve precise oncologic control of recurrent disease while maintaining urinary and sexual function. Regulatory studies examined TULSA in treatment-naïve patients; outcomes of TULSA as a salvage therapy for recurrent disease are not well established. We report safety and early oncologic outcomes of salvage TULSA in patients with recurrent prostate cancer following prior local treatment.

Materials and Methods: A retrospective analysis was performed in PCa patients with ≥6-month follow-up after salvage TULSA in an outpatient center. Ablation plan was defined according to patient preference and disease factors using intraoperative DWI, ADC, and T2w imaging. Patients were followed daily for 2 weeks, PSA at 3 months, with MRI, IPSS, and SHIM at 6-9 months. Radiologic recurrence was defined as PI-RR≥4 on mpMRI, or positive PSMA-PET after PI-RR=3. Biochemical recurrence (BCR) was defined as PSA nadir + 2 ng/mL.

Results: Forty-five patients with recurrent PCa were identified: 39/45 after focal therapy (FLA: 22, TULSA: 16, HIFU: 1) and 6/45 after radiation (proton: 4, brachytherapy: 2). Median age was 67 years (IQR 64–71), with 18 months (12–27) median follow-up. Post-primary treatment biopsy (n=31) showed GG1–5 in 6%, 39%, 32%, 16%, and 6%. All patients had a visible lesion on MRI, and median gland volume was 30 cc (IQR 24–40, range 11–81). Whole-gland ablation was performed in 73% of patients, focal in 27%. Outcomes after whole-gland vs. focal ablation: median PSA nadir 0.7 (0.2–1.8) vs. 0.9 ng/mL (0.3-1.2) ng/mL, gland reduction 61% (44–67) vs. 30% (22-33). Overall, 87% were free of radiologic/biochemical recurrence. Five patients had residual disease on MR: three had persistent T3 disease, and two had disease related to inadequate planning margins. Urinary symptoms (IPSS) were stable. All patients remained pad- and leak-free at follow-up. Of 33 men potent before salvage TULSA, 82% preserved erections sufficient for penetration (SHIM Q2≥2).

Conclusion: Our findings suggest that salvage TULSA is a safe and effective option for patients with recurrent prostate cancer.