Selective Arterial Prostatic Embolization (SAPE) for the Treatment of Lower Urinary Tract Symptoms in the Setting of Benign Prostatic Hyperplasia: A Brief Review

Abstract

Tel: 212-241-9955 Benign prostatic hyperplasia (BPH) is a common condition related to aging that can lead to a cluster of chronic symptoms collectively known as lower urinary tract symptoms (LUTS), including urinary frequency, urinary urgency, nocturia, hematuria, and decreased urinary stream. It is estimated that BPH affects 75% of men in the United States by age 70, with more than $1 billion US dollars a year spent in direct health care expenditures related to BPH, exclusive of outpatient medications [1]. Treatment options for BPH are outlined out by the American Urologic Association Clinical Guidelines and include watchful waiting, medical therapy, minimally invasive therapies (including transurethral ablations), or surgical therapies including open prostatectomy or transurethral resection of the prostate (TURP) [2]. Medical therapy is often considered the first-line option for symptomatic patients; however, a large subset of patients does not respond to or cannot tolerate pharmacotherapy, in part owing to a number of side effects including sexual dysfunction [3]. TURP has remained the ‘gold standard’ surgical treatment for BPH for over half a century, owing to its high success rate in reducing LUTS. Over the past two decades, the TURP procedure has undergone significant technical improvements, with morbidity rates reported to be <1% [4]. However, with a general shift towards minimally invasive treatment options, the number of TURPs performed has fallen in more recent years [5]. Manuscript Click here to download Manuscript SAPE final (1).docx Embolization of the prostatic arteries has been used for many years as a technique to control severe bladder and prostate hemorrhage as well as hematuria following TURP [6-9]. A case report by DeMeritt et al in 2000 described a patient with BPH and refractory hematuria treated by prostatic artery embolization, who subsequently had alleviation in his LUTS and reduction in the volume of his prostate [10]. This case report introduced the idea that BPH could intentionally be treated by selective arterial prostatic embolization (SAPE). In 2008, Carnevale et al used SAPE as the primary treatment in two patients with BPH [11]. After 6-month follow-up, MRI demonstrated a relative prostate reduction of 47.8% in the patient who had undergone bilateral SAPE and 27.8% in the patient who had undergone unilateral SAPE. Since this initial study, there has been an enthusiastic response in the literature regarding the future role of this technique, and the Society of Interventional Radiology has encouraged further research into this intervention [12]. A growing body of literature suggests that SAPE enables reduction in prostate volume with improvements in uroflometry parameters, quality of life, and sexual function [13]. The largest prospective non-randomized series published to date looked at 255 patients who underwent SAPE [14]. The authors describe technical success in 250 of the patients (98%), with a clinical success rate of 82% at one month decreasing to 72% at 3 years. In the only RCT to date assessing SAPE, 57 patients were assigned to prostatic artery embolization and 57 were assigned to TURP for the treatment of BPH [15]. The authors demonstrated that all parameters: including improvement of the International Prostate Symptom Score (IPSS), quality of life (QOL), peak urinary flow, and post void residual(PVR) urine volume were improved by both treatment modalities and there was no difference at two years between the treatment arms. The paper does state there was a higher complication rate for PAE, if one controls for acute urinary retention post operatively, there would be similar complication rates for both groups. The technique for SAPE involves unilateral access of the femoral artery and subsequent catheterization of the anterior division of the internal iliac artery. Digital subtraction angiography is used to confirm arterial anatomy and allow for superselective catheterization of the prostatic artery. A number of different embolic materials have been used, including polyvinyl alcohol particles, trisacryl gelatin microspheres, and Embozene Selective Arterial Prostatic Embolization (SAPE) for the Treatment of Lower Urinary Tract Symptoms in the Setting of Benign Prostatic Hyperplasia: A Brief Review