Cryoablation of Prostate- Improving Efficacy and Safety

Abstract

Cryoablation has been shown to be an effective therapy for all stages of prostate cancer. Though judged efficacious, complications of treatment and persistent disease, although minimal, show the need for improvement. To this end, research has focused on new technology design for cryosurgical apparatus and imaging techniques. Adjunctive therapy, focusing on increasing cell death by apoptosis, also plays a role in this new direction with the intent of increasing cell death in the frozen tissue. Additionally, incorporating methods of protecting adjacent structures, including the urethra, bladder neck sphincter, urogenital diaphragm, neurovascular bundles, and rectum, are critical to achieving a successful outcome and continue to evolve. Several strategies to protect these structures are now commonplace as part of a cryosurgical procedure. These strategies include real-time temperature monitoring, visualization of ice growth during freezing, active heating and even the injection of protective media have emerged as methods to protect these structures. Another more recent procedural application is partial gland ablation or image-targeted focal therapy, developed to maintain cancer control yet minimize the risk of collateral damage to the various structures. Each of these methods has been shown in vitro, in vivo, and clinically to be beneficial. This article describes the directions that cryoablation has taken in an effort to improve procedural efficacy while reducing/eliminating associated co-morbidities.