Safety and efficacy of MRI-guided transurethral ultrasound ablation for radiorecurrent prostate cancer in the presence of gold fiducial markers

Background Safety and efficacy of ultrasound prostate ablation for radiorecurrent prostate cancer (PCa) in the presence of gold fiducial markers has not been previously reported. Purpose To evaluate safety, functional, and early-stage oncological outcomes for patients with gold fiducial markers undergoing salvage magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (sTULSA) for radiorecurrent PCa. Material and Methods Data were acquired from an ethics-approved, single-center phase-1 study. Eight patients with 18 total gold fiducial markers inside the planned treatment volume were identified. MRI controls were performed at three and 12 months, followed by PSMA-PET-CT imaging and biopsies at 12 months. A control cohort of 13 patients who underwent sTULSA without markers were also identified for safety profile comparison. Adverse events were reported using the Clavien-Dindo classification, and questionnaires including EPIC-26, IPSS, and IIEF-5 were collected. Results Of 18 markers, 2 (11%) were directly responsible for poor ultrasound penetration. However, there were no local recurrences at 12 months. PSA, prostate volume, and non-perfused volume all decreased over time. At 12 months, 11/18 (61%) of fiducial markers had disappeared via sloughing. The adverse event profile was similar between both patient cohorts, and when controlled for ablation type, no statistical difference in functional outcomes between the two cohorts was observed. Conclusion Patients with radiorecurrent PCa with intraprostatic gold fiducial markers can be successfully treated with TULSA. The early-stage efficacy of sTULSA for patients with intraprostatic gold markers is encouraging and the safety profile is unaffected by marker presence.