Bladder function after conservative surgery and high-dose rate brachytherapy for bladder-prostate rhabdomyosarcoma

Background Conservative surgery (CS) brachytherapy (BT) techniques for local therapy in bladder-prostate rhabdomyosarcoma (BP-RMS) seek to retain organ function. We report bladder function after high-dose rate (HDR) BT combined with targeted CS for any vesical component of BP-RMS. Procedure Prospective cohort of all BP-RMS patients between 2014 and 2019 receiving HDR-BT (iridium-192, 27.5 Gy in five fractions) with/without percutaneous endoscopic polypectomy (PEP) or partial cystectomy (PC). Functional assessment included frequency-volume chart, voided volumes, post-void residual, flow studies, continence status and ultrasound scanning; abnormalities triggered video urodynamics. Results Thirteen patients (10 male), aged 9 months to 4 years (median 23 months), presented with localised fusion-negative embryonal BP-RMS measuring 23-140 mm (median 43 mm) in cranio-caudal extent. After induction chemotherapy, local treatment consisted of PC+BT in three, PEP+BT in four and BT alone in six. At a median 3.5 years (range 21 months to 7 years) follow-up, all were alive without relapse. At a median age of 6 years (4-9 years), the median bladder capacity was 86% (47%-144%) of that expected for age, including 75% (74%-114%) after PC. Radiation dose to the bladder was associated with urinary urgency, but not bladder capacity or nocturnal enuresis. Complications occurred in two: one urethral stricture and one vesical decompensation in a patient with pre-existing high-grade vesico-ureteric reflux (VUR). The remaining patients were dry by day; five with anticholinergic medication for urinary urgency. Three patients are enuretic. Conclusions Day-time dryness at a median 3.5 years after CS-HDR-BT was achieved in 92%, with 85% voiding urethrally, and 62% attaining day-and-night continence aged 4-9 years. We report reduced open surgery with minimally invasive percutaneous surgery, with HDR-BT or BT alone being suitable for many.