Leiomyoma of the bladder presenting as acute urinary retention in a female patient: urodynamic analysis of lower urinary tract symptom; a case report

Abstract

Background: Most bladder tumors are derived from the urothelium. Benign mesenchymal tumors are rare. Leiomyoma of the bladder is the most common benign neoplasm. We present a case of leiomyoma of the bladder presenting with acute urinary retention in a female patient and report on the post-operative change in urodynamic findings. To our knowledge, few cases of this kind have been reported.

Case presentation: A 56-year-old woman presented with acute urinary retention. Evaluations including ultrasound, magnetic resonance imaging, cystoscopy, and urodynamics contributed to a diagnosis of leiomyoma of the bladder. Various medications were ineffective for solving her lower urinary tract symptoms; therefore, a transurethral resection was performed. The final pathological report was leiomyoma. After the operation, her symptoms resolved; this improvement was confirmed by an urodynamic analysis. The postoperative urodynamics demonstrated a lower frequency of detrusor overactivity during filling cystometry and an increase in the uroflow rate, with reduced detrusor pressure in a pressure flow study.

Conclusions: Leiomyoma of the bladder can cause female outlet obstruction. A review of the literature and disease management is discussed.

Figure 1

Sagittal section of a magnetic resonance image. Sagittal section of a magnetic resonance image shows a homogeneous mass (2.7 cm in diameter) occupying the area between the bladder neck and the anterior vaginal wall. The tumor mass was homogenously enhanced after the injection of gadolinium.

Figure 2

Histopathological examination. a, b) Histopathological examination of the tumor specimen shows a proliferation of spindle-shaped cells with eosinophilic cytoplasm and fibers (H&E). No evidence of mitotic figures or atypia was seen. c, d) Immunohistochemistry revealed positive staining for smooth muscle actin (c) and negative staining for Ki-67 (d). The tumor was diagnosed as a leiomyoma.

Figure 3

Cystometry and pressure-flow study (pre-TUR and post-TUR). a) Preoperative-UDS: Three involuntary detrusor contractions occurred at 42, 138, and 160 mL during filling. She voided with a Q_max of 4 mL/sec and a P_det of 177 cmH₂O. These values suggested female BOO. b) Postoperative UDS: Only one involuntary detrusor contraction occurred at 286 mL, just before voiding. Her maximum desire-to-void volume increased to 306 mL. She voided with a Q_max of 15 cm/s and a P_det of 62 cmH₂O. A postoperative PFS demonstrated a considerable improvement in voiding. Q: flow, P_ves: vesical pressure, P_abd: abdominal pressure, P_det: detrusor pressure, red arrows: voluntary bladder contraction.