A multi-institutional critical assessment of dorsal onlay urethroplasty for post-radiation urethral stenosis

Abstract

To critically evaluate a multi-institutional patient cohort undergoing Dorsal-Onlay Buccal Mucosal Graft Urethroplasty (D-BMGU) for recurrent post-radiation posterior urethral stenosis. Retrospective multi-institutional review of patients with posterior urethral stenosis from 10 institutions between 2010-2019 was performed. Patients with at least 1-year follow-up were assessed. Patient demographics, stenosis characteristics, peri-operative outcomes, and post-operative clinical and patient-reported outcomes were analyzed. The primary outcomes were stenosis recurrence and de-novo stress urinary incontinence (SUI). Secondary outcomes were changes in voiding, sexual function, and patient-reported satisfaction. Seventy-nine men with post-radiation urethral stenosis treated with D-BMGU met inclusion criteria. Median age and stenosis length were 72years, (IQR 66-75), and 3.0cm (IQR 2.5-4cm), respectively. Radiation modalities included: 36 (45.6%) external beam radiotherapy (EBRT), 13 (16.5%) brachytherapy (BT), 10 (12.7%) combination EBRT/BT, and 20 (25.3%) EBRT/radical prostatectomy. At a median follow-up of 21months (IQR 13-40), 14 patients (17.7%) had stenosis recurrence. Among 37 preoperatively-continent patients, 3 men (8.1%) developed de-novo SUI following dorsal onlay urethroplasty. Of 29 patients with preoperative SUI all but one remained incontinent post-operatively (96.6%). Following repair, patients experienced significant improvement in PVR (92.5 to 26cc, p = 0.001) and Uroflow (4.6 to 15.9cc/s, p = 0.001), and high overall satisfaction, with 91.9% reporting a GRA of + 2 or better). Dorsal onlay buccal mucosa graft urethroplasty is a safe and feasible technique in patients with post-radiation posterior urethral stenosis. This non-transecting approach may confer low rates of de-novo SUI. Further research is needed to compare this technique with excisional urethroplasty.