Continent Urinary Diversion Using the Mitrofanoff Principle Following Urethrectomy for Primary Vaginal Melanoma: A Case Report

Abstract

Primary vaginal malignant melanoma is an extremely rare and aggressive cancer, accounting for less than 3% of melanomas involving the female genital tract. Due to its nonspecific presentation, diagnosis is often delayed, and no standardized treatment protocol exists. A 63-year-old postmenopausal woman presented with persistent vaginal discharge, anorexia, and weight loss. Clinical evaluation and biopsy of a vaginal lesion revealed malignant melanoma. Magnetic resonance imaging demonstrated vaginal and urethral involvement. Histopathology revealed malignant melanoma, positive for S-100, SOX-10, vimentin, and focal HMB-45. Following a multidisciplinary evaluation, she underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, total vaginectomy, urethrectomy, and Mitrofanoff (appendicovesicostomy) urinary diversion. Histopathology confirmed melanoma with a Breslow thickness of 4 mm and negative margins. She received adjuvant pelvic radiotherapy and was trained in clean intermittent self-catheterization (CISC). At 33 months post-treatment, the patient remains disease-free and functionally independent, with successful CISC. This case emphasizes the role of individualized surgical planning and continent urinary reconstruction following urethrectomy in the management of locally advanced vaginal melanoma. A multidisciplinary approach and individualized intervention are essential to optimize outcomes in such rare gynecologic malignancies.