Targeted and precise application of thermal energy stored in sterile water vapor is a novel approach to treat cancerous prostate tissue. We report safety and oncological results of transurethral hemigland vapor ablation in a prospective, single-arm study in men with unilateral, intermediate-risk localized prostate cancer.
Men with biopsy confirmed Gleason Grade Group 2 (GG2) adenocarcinoma of the prostate, mean age 64.6 years, PSA 5.2 ng/mL, and prostate volume 46.8 cc on TRUS were enrolled. Using cystoscopy and transrectal ultrasound (TRUS) guidance, water vapor (~103°C) was delivered to prostate zones for hemigland ablation inclusive of cancers identified by multiparamertric MRI (mpMRI) and biopsy. At 6-months, combined 12-core systematic and mpMRI fusion biopsy was performed. Subjects with no remaining GG2 disease were followed for 12 months. Those with residual or newly identified GG2 disease were eligible for a second vapor ablation and subsequent 6-month mpMRI fusion biopsy and were followed for at least 18 months after index treatment.
Fifteen subjects were successfully treated. At 6 months 4/15 subjects were identified for further management, two with residual GG2 cancer on the treated side, and two with newly identified GG2 cancer on the untreated contralateral side; one of two subjects with residual GG2 was ineligible for retreatment (unrelated myocardial infarction). Follow up at 12 to 18 months after initial or retreatment provided a final ≥GG2 negative biopsy in 14/15 (93.3%) subjects. Device or procedure-related adverse events (AEs) were mild/moderate and transient; none were serious AEs.
Water vapor ablation has low morbidity. It is possible to successfully retreat residual disease or new lesions identified on surveillance with only transient mild to moderate adverse events and acceptable oncologic outcomes offering a new management strategy for localized prostate cancer.
Treatment decisions for men with localized prostate cancer (PCa) are determined with consideration of multiple factors including, disease risk, co-morbidities, estimated life-expectancy and each patient’s preferences. Currently, many men with low-risk disease are offered active surveillance, during which the prostate cancer is closely monitored for any changes, whereas men with intermediate or high-risk localized cancers are more often considered for surgical removal of the prostate or treatment with radiation. This study was conducted to evaluate a novel therapy designed to destroy PCa tissue using water vapor ablation in men with intermediate-risk PCa confined to one side of the prostate. Dr. Warlick et al used this new technology to treat tumors that were visible under magnetic resonance imaging (MRI) and confirmed to be cancerous via biopsy. The study also includes results from a subset of patients that received additional treatments of newly identified cancer in previously untreated areas on the other side of the prostate, or retreatment of residual (missed) cancer after the initial procedure. Patients experienced no serious side effects after treatment. Results of this feasibility study support further exploration of this new therapeutic procedure and the opportunity it may offer to men to manage their localized prostate cancer through surveillance and additional therapy as needed.
Research and reports in urology. 2025 Feb 03*** epublish ***
Christopher A Warlick, Benjamin D Spilseth, Christopher M Dixon
Department of Urology, University of Minnesota, Minneapolis, MN, USA., Department of Radiology, University of Minnesota, Minneapolis, MN, USA., WMC Health Good Samaritan Hospital, Bon Secours Urology, Suffern, NY, USA.