Transurethral Needle Ablation of the Prostate

Abstract

There has been considerable interest over the past decade in the development of nonsurgical and minimally invasive therapies for benign prostatic hyperplasia (BPH), especially for patients who do not desire surgery or for those who are poor surgical candidates. Transurethral resection of the prostate (TURP) remains the most effective and durable endoscopic therapy for symptomatic BPH, but it has been associated with potentially significant morbidity (1). A meta-analysis of patients undergoing TURP estimated that 30.7% of patients experienced some morbidity or complication (2). Borboroglu et al. reported on a series of 520 patients who underwent TURP from 1990 to 1998 and had immediate and late complication rates of 10.8% and 8.5%, respectively (3). Approximately 15% of patients require a second intervention within 10 yr of undergoing TURP (4). The combination of patient demands and socioeconomic concerns has spurred the increased interest in less invasive, less morbid treatment options for BPH. Medical therapies such as α-blockers and 5α-reductase inhibitors as well as balloon dilation, urethral stents, and thermal therapies have been the focus of attention. Various thermal strategies have been investigated as minimally invasive procedures for BPH, including the use of microwave, laser, high-intensity focused ultrasound, and radiofrequency (RF) energy to deliver heat to the interstitium of the prostate. All thermotherapies, regardless of the form of energy used, achieve necrosis of the prostate by raising the temperature of the tissue to above 60° C (5). Transurethral needle ablation of the prostate (TUNA) uses low-energy RF delivered directly into the prostate to produce controlled necrosis of the obstructing adenoma. RF has been used successfully in other medical applications such as to ablate accessory atrioventricular bundles in Wolff-ParkinsonWhite syndrome and to destroy neoplastic hepatocellular tumors and anomalous neural tissue (6–8). For the past decade, TUNA has been investigated as a minimally invasive alterative to TURP for the management of symptomatic BPH. The precision of the RF delivery and the reproducible necrosis have made TUNA an attractive alternative to more invasive surgery.