Multidisciplinary Treatment of Abdominal Wall Recurrence After Bladder Perforation During Transurethral Resection of a Bladder Tumor

Introduction: Sarcomatoid urothelial carcinoma is a rare, highly aggressive bladder cancer subtype. We report the first case of abdominal wall implantation of sarcomatoid urothelial carcinoma after bladder perforation during transurethral resection of a bladder tumor, followed by recurrence at the open repair site requiring further resection. Case Presentation: A 73-year-old woman underwent emergency transurethral resection for a rapidly enlarging bladder tumor complicated by full-thickness perforation. Histopathology revealed sarcomatoid urothelial carcinoma. During intravesical bacillus Calmette-Guérin therapy, she developed a malignant right lower abdominal wall mass attributed to tumor implantation. Enfortumab vedotin plus pembrolizumab did not prevent progression. Preoperative radiotherapy was followed by en bloc resection with partial cystectomy and anterolateral thigh flap reconstruction. Pathology demonstrated extensive treatment-related necrosis and negative margins. She remained recurrence-free at 11 months. Conclusion: For localized recurrence, aggressive multidisciplinary treatment incorporating radical local resection and reconstructive surgery may provide local disease control in selected patients without metastasis.