One-year Follow-up after US-guided Transperineal Focal Laser Ablation of Localized Prostate Cancer: Worldwide Registry Study

Background Despite growing research interest in focal therapies for localized prostate cancer (PCa) tumors, no large cohort studies have evaluated the oncological outcomes of US-guided transperineal focal laser ablation (TPLA). Purpose To evaluate the 12-month oncological outcomes of MRI-directed US-guided TPLA in patients with localized PCa. Materials and Methods Patient data from four centers in Europe and the United States (May 2018 to July 2023) were retrospectively analyzed. Single-fiber or multifiber TPLA was performed (1064 nm, 3-5 W) for biopsy-confirmed, MRI-delineated Prostate Imaging Reporting and Data System (PI-RADS) 3 or higher lesions. The minimum follow-up was 12 months and included prostate-specific antigen (PSA) and PSA density (PSAD) measurements, MRI, and protocolized or MRI-indicated biopsy. MRI positivity was defined as a PI-RADS 3 or higher lesion at follow-up imaging. In-field recurrence (IFR) was defined as biopsy-proven PCa within the treated area; the IFR of clinically significant PCa (csIFR) was defined as a Gleason score (GS) of at least 3+4. Predictors of csIFR were assessed at three predefined stages (preoperative, perioperative, and postoperative). Stage-specific mixed-effects multivariable analyses were conducted with variables that were statistically significant in univariable analysis after accounting for known predictors. Results Overall, 195 men (median age, 69 years; IQR, 63-74 years) underwent TPLA for 206 lesions, of which 32% were GS 3+3, 48% were GS 3+4, 29% were GS 4+3, and 7% were GS 4+4. The median initial PSA level was 6.8 ng/mL (IQR, 5.4-9.0 ng/mL), and the median tumor length was 11 mm (IQR, 9-14 mm). csIFR was detected in 36 of the 206 (17%) lesions, with an overall IFR rate of 49 of 206 (24%). An initial PSAD greater than 0.16 ng/mL2 was an independent preoperative predictor of csIFR (odds ratio [OR]: 2.62; 95% CI: 1.01, 6.89; P = .049). Postoperatively, positive MRI findings were predictive of csIFR (OR: 67.87; 95% CI: 18.74, 246.01; P < .001), with 83% sensitivity and 89% specificity. Conclusion In this multicenter study, MRI-directed, US-guided TPLA of 206 localized PCa lesions resulted in a 12-month csIFR rate of 17%. Post-TPLA positive MRI findings were highly predictive for csIFR. ClinicalTrials.gov identifier: NCT05163197 © RSNA, 2026 Supplemental material is available for this article.