病例報告：膀胱平滑肌瘤

吳冠賢^1,2, 李香瑩^1,2,3*

¹高雄醫學大學附設中和醫院 泌尿部、²高雄醫學大學 臨床醫學研究所、^３高雄醫學大學醫學系 泌尿學科

Leiomyoma of Urinary Bladder: A case report

Kuan-Hsien Wu^1,2, Hsiang-Ying Lee^1,2,3*

¹Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan

²Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan

³Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan

Introduction: The occurrence of benign bladder tumors is relatively uncommon. Among these rare cases, leiomyoma accounts for an exceptionally small percentage, representing less than 0.5% of all bladder tumor cases. These non-cancerous growths originate from the smooth muscle cells of the bladder wall and can present with various symptoms depending on their size and location within the bladder. Despite their rarity, it is crucial to distinguish leiomyoma from their malignant counterparts through appropriate diagnostic procedures, as the treatment approach and prognosis can differ significantly. Through this clinical case, we explore a comprehensive understanding of leiomyoma through different aspects.

Case report: A 34-year-old woman denied any underlying disease. During the prenatal checkup in the obstetrics and gynecology department, a bladder tumor was found incidentally under the ultrasound survey. She denied having fever, other urinary or gastrointestinal symptoms, and any contact history. Urine analysis revealed microscopic hematuria. Cystoscopy showed a bladder mass at left lateral wall. A contrast computed tomography (CT) scan of the abdomen depicted left lateral urinary bladder basal tumor mass 3.35cm beneath ureterovesical junction. Transurethral resection of bladder tumor was performed. The patient recovered well after the surgery. The pathologic diagnosis was leiomyoma. Microscopically, section shows proliferative smooth muscle cells with blunt-ended nuclei and abundant eosinophilic cytoplasm, arranged in intersecting fascicles. Immunohistochemical analysis revealed positive for desmin. No obvious recurrent tumor was found during further cystoscopy follow up.

Conclusion: Leiomyoma of bladder is a rare benign neoplasm. Patients are often diagnosed accidentally due to the indolent clinical behavior. The diagnosis of bladder leiomyoma primarily relies on pathological examinations, including cytogenetic and immunohistochemical studies. Surgical resection is vital to long-term survival. Through this clinical case, we aim to enhance understanding of the diagnosis and treatment of this tumor.