How to cite: George AK. “Water Vapor Thermal Therapy for Prostate Cancer.” Grand Rounds in Urology. October, 2025. Accessed Apr 2026. https://grandroundsinurology.com/water-vapor-thermal-therapy-for-prostate-cancer/
Summary
Arvin K. George, MD, Director Prostate Cancer Programs, Associate Professor of Clinical Urology, Johns Hopkins University, Baltimore, Maryland, describes the mechanism of water vapor thermal therapy and its potential translation from BPH treatment to prostate cancer ablation. He explains that conventional thermal therapies rely on conduction with progressive heat spread through tissue volumes. In contrast, water vapor thermal therapy utilizes convection. This phase change produces rapid energy delivery and allows the vapor to travel within natural anatomic planes. Normal zonal boundaries of the prostate limit vapor spread, ensuring treatment remains within defined anatomic segments.
He illustrates how commercially available water vapor therapy for BPH creates thermal lesions confined to the transition zone or central zone while preserving adjacent structures. Contrast-enhanced imaging demonstrates treated regions and viable peripheral zones. Building on this experience, he notes that prostate cancer can arise in any zone, so a cancer-focused program must treat the disease in the peripheral zone as well as the transition and central zones. He demonstrates that vapor-based ablation can produce unilateral peripheral zone ablation, bilateral peripheral ablation, combined transition and peripheral ablation on one side, or whole-gland ablation as needed.
Dr. George then outlines the design of the VAPOR2 study. The program includes a component that seeks a prostate tissue ablation indication and a cancer management component that evaluates effectiveness over several years. The cancer management endpoint focuses on eliminating Grade Group 2 disease. Glands are limited to a moderate size range, and patients must have targeted and systematic fusion biopsy confirmation without high-risk imaging features. The design allows for in-field retreatment and regional ablation of new sites identified through core tracking. Dr. George states that water vapor thermal therapy is standard of care for BPH and remains investigational for prostate cancer, with VAPOR2 positioned to define its role in regional cancer control.
Frontiers in Oncologic Prostate Care and Ablative Local Therapy (FOCAL) is an outstanding program on prostate imaging, transperineal interventions, and ablative treatments for prostate cancer and benign prostatic hyperplasia. Bringing together community-based, academic, and industry partners, FOCAL offers lectures by world-renowned faculty and hands-on training workshops on in-office transperineal interventions, fusion-guided prostate ablation and state-of-the-art BPH management with novel technologies.
ABOUT THE AUTHOR
Arvin K. George, MD, serves as Director of Prostate Cancer Programs and Associate Professor (PAR) of Urology at Johns Hopkins School of Medicine in Baltimore, Maryland. He is a urologic surgeon who specializes in the diagnosis and management of genitourinary cancers. After obtaining his medical degree from the Royal College of Surgeons in Ireland, he completed his urology residency at the Smith Institute for Urology at the Hofstra North Shore-LIJ School of Medicine. He remained there to complete his endourology fellowship in New York, gaining additional subspecialty expertise in robotic, laparoscopic, and percutaneous surgery. Subsequently, he completed a urologic oncology fellowship at the National Cancer Institute of the National Institutes of Health. Dr. George’s research interests include minimally-invasive and image-guided treatments, functional prostate imaging, and focal therapy for prostate cancer. His research aims to identify appropriate use for imaging in diagnosis, risk stratification, and management of prostate cancer, including active surveillance and selection/treatment of patients with novel focal therapy modalities.
