TY - EJOU AU - Hou, Changhao AU - Zhang, Ruihang AU - Luo, Pengbo AU - Zhu, Weidong AU - Song, Lujie TI - Gracilis muscle flap for salvage repair of radiation-induced urethroperineal fistula after rectal cancer surgery: a case report T2 - Canadian Journal of Urology PY - VL - IS - SN - 1488-5581 AB - Background: Urethroperineal fistula (UPF) is a rare urological condition with significant heterogeneity and limited treatment consensus. Especially in patients with a history of radiotherapy, extensive tissue damage often leads to insufficient local tissue reconstruction. Case Description: A 61-year-old male with a history of rectal cancer radiotherapy and abdominoperineal resection developed UPF, which recurred after robot-assisted prostatectomy combined with perineal fistula repair and scrotal dartos flap interposition. Imaging confirmed a 2 cm × 3 cm fistula defect at the prostatic urethra stump. We performed gracilis muscle flap transfer to repair UPF. Postoperative follow-up included urethrography, cystoscopy, and patient-reported outcome measures. At 1-year follow-up, the fistula was resolved without recurrence; the patient underwent artificial urinary sphincter implantation for pre-existing incontinence, achieving satisfactory urinary control and no limb mobility impairment. Conclusions: Surgical outcomes and long-term follow-up confirmed the efficacy of the procedure and high patient satisfaction. The key lessons include thorough scar excision for vascularization, and meticulous preservation of the gracilis muscle’s neurovascular pedicle to ensure flap viability. KW - case report; urethroperineal fistula; gracilis muscle flap; radiation-induced; rectal cancer DO - 10.32604/cju.2026.073870