MRI-Guided Transurethral Ultrasound Ablation in Patients with Localized Prostate Cancer: Three Year Outcomes of a Prospective Phase I Study.

Nair, Shiva M; Hatiboglu, Gencay; Relle, James; Hetou, Khalil; Hafron, Jason; Harle, Christopher; Kassam, Zahra; Staruch, Robert; Burtnyk, Mathieu; Bonekamp, David; Schlemmer, Heinz-Peter; Roethke, Matthias C; Mueller-Wolf, Maya; Pahernik, Sascha; Chin, Joseph L

OBJECTIVES To report the three-year follow-up of a Phase I study of magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) in 30 men with localized prostate cancer. Favorable 12-month safety and ablation precision were previously described. MATERIALS AND METHODS As a mandated safety criterion, TULSA was delivered as near whole-gland ablation, applying 3-mm margins sparing 10% of peripheral prostate tissue. After 12-month biopsy and MRI, biannual follow-up included prostate-specific antigen (PSA), adverse events, and functional quality of life assessment, with repeat systematic biopsy at three years. RESULTS Three-year follow-up was completed by 22 patients. Between one and three years, there were no new serious or severe adverse events. Urinary and bowel function remained stable. Erectile function recovered by one year, stable at three years. PSA decreased 95% to median (IQR) nadir of 0.33 (0.1-0.4)ng/ml, stable to 0.8 (0.4-1.6)ng/ml at three years. Serial biopsies identified clinically significant disease in 10/29 men (34%), any cancer in 17/29 (59%). By three years, seven men had recurrence (four histological, three biochemical) and had undergone salvage therapy without complications (including six prostatectomy). At three years, 3/22 men refused biopsy, and 2/22 (9%) had clinically significant disease (one new, one persistent). Predictors of salvage therapy requirement included less extensive ablation coverage and higher PSA nadir. CONCLUSION With three-year Phase I follow-up, TULSA demonstrates safe and precise ablation for men with localized prostate cancer, providing predictable PSA and biopsy outcomes, without affecting functional abilities or precluding salvage therapy.