Transperineal MR Fusion Laser Ablation of Prostate Cancer in Office Setting: 1 Year Efficacy and Safety Outcomes in Intermediate-Risk Patients.

Abstract

Introduction: Focal therapy (FT) is an emerging option for intermediate-risk prostate cancer (IR-PCa). Transperineal MRI fusion laser ablation of PCa (TPFLA) is a novel FT technique with limited data reported. We conducted a phase I clinical trial evaluating the safety, feasibility, and 1-year oncologic results for patients with IR-PCa treated with TPFLA in an office setting. Materials and Methods: NCT05241236 aimed to evaluate TPFLA for the International Society of Urological Pathology-grade 2 (ISUP-2) tumors. All procedures were performed in the office using MR/US fusion imaging. The diode interstitial laser system fibers were applied through the perineum using local anesthesia. The primary outcome was safety and tolerability. Pain scores were recorded using analog scales. Thirty-day adverse events and 1-year prostate biopsy oncologic outcomes were noted. Functional outcomes at 3 months and 1 year were compared with baseline as well. Results: Thirty patients accrued had TPFLA safely in the office with no complications. TPFLA median pain score was 1. At 30 days, one man required a transurethral resection of the prostate (TURP). There were no imaging demonstrable cancers at 3 months and a significant improvement in urinary function (p = 0.001) was noted and sustained for the year. No patient experienced urinary incontinence. No changes in sexual function were observed (p = 0.7). At 1 year, 25/30 (83%) had no clinically significant cancer. However, 14 had PCa, in 5 (17%) solely in treated areas, all ISUP-1. Seven had PCa outside the treated areas. Two had infield and outfield recurrences, both were ISUP 2. At study closure, 16 patients were free from PCa, 3 were on active surveillance, 9 were treated focally with cryoablation, and 2 were converted to radical surgical procedure. Conclusions: TPFLA appears to be a safe and an effective focal therapy for IR-PCa, offering a potential alternative to more radical treatments with a minimal periprocedural impact. Longer follow-up and larger studies are needed to confirm these results.