Prostatic stents: a narrative review of current evidence.

Benign prostatic hyperplasia (BPH) is a common chronic urologic condition affecting approximately 50% of men above the age of 60. As per European Association of Urology Guidelines, BPH can be treated according to a stepwise approach starting from a conservative management, a pharmacologic approach, and finally surgery. Both medical and surgical therapies have side effects, impacting on ejaculation and sexual function and patients with multiple comorbidities might not be considered surgically suitable candidates. Prostatic stents offer a minimally invasive procedures in an out-patient setting, possibly under local anaesthesia. Utilized since the 1980s, the past stents encompassed permanent (epithelializing) or temporary (non-epithelializing) devices, like the Uro-Lume (American Medical Systems, Minnetonka, MN, USA) and the Memokath, or Memotherm (Engineers & Doctors A/S, Denmark), and the biodegradable stents made of self-reinforced poly-L-lactide or braided poly lactic-co-glycolic acid. Previous stents however showed a quite high rate of complications among which pain, incontinence, infections, stent migration or blockage, and incomplete degradation that might lead to premature removal of stent. The stents currently available on the market instead are the temporary device Allium Triangular Prostatic Urethral Stent (Allium Urological Solutions, Caesarea, Israel) and the temporary stent SPANNER (AbbeyMoor Medical, Inc., Parkers Prairie, MN, USA), which might be used in case of bladder outflow obstruction, post-operatively, or for acute urinary retention. Studies showed encouraging results, in terms of effectiveness and safety improving patients' quality of life and International Prostate Symptom Score, but longer-term studies are needed to identify the most suitable patients who might benefit from their use. Newer stents and nitinol devices are currently investigated, and we are waiting for the results of the ongoing clinical trials.