Background
Most bladder tumours are derived from the urothelium. Benign mesenchymal tumours are rare and comprise 1 to 5% of all bladder neoplasms1. Among them, leiomyoma is the most common benign neoplasm, accounting for 0.43% of bladder tumours2. Approximately 75% of the patients are young or middle aged3. We present a case of leiomyoma of the bladder with acute urinary retention in a female patient and report on the urodynamic changes after transurethral resection (TUR). A literature search of PubMed using the terms leiomyoma of the bladder and urodynamics suggested that only one other case of a bladder leiomyoma with acute urinary retention in a female patient who was evaluated using urodynamics has been previously published4. To our knowledge, there are few cases describing an urodynamic evaluation of a female patient with a bladder leiomyoma. Here, we present and discuss an exemplary case of lower urinary tract symptom (LUTS) caused by a leiomyoma of the bladder.
Case Presentation
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| 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 tumour mass was homogenously enhanced after the injection of gadolinium. |
A 56 year old woman presented at our hospital with an episode of acute urinary retention. She also complained of urinary frequency and urgency for the past four months. A physical examination did not reveal any particular findings, including pelvic organ prolapse. The results of a laboratory evaluation were within the normal limits. The urinary cytology was class II. In our cytology system, a scale of 1 – 5 was used. An ultrasonography detected a round mass in the bladder and no signs of hydronephrosis. A cystoscopy revealed a smooth surface and an intact mucosa tumour at the bladder neck. Magnetic resonance imaging (MRI) demonstrated a homogenous mass measuring 2.7 cm in diameter occupying the space between the bladder neck and the anterior vaginal wall. The tumour was homogenously enhanced after the injection of gadolinium (Figure 1).
From these finding, we suspected a leiomyoma of the bladder. To confirm this diagnosis, we performed a transvaginal needle biopsy under ultrasonic guidance; however, the histological studies were unable to provide a diagnosis because of inadequate tissue collection during the biopsy.
The patient was treated with an anti-cholinergic agent and an alpha-blocker for two months, but her LUTS symptoms did not resolve. Therefore, we performed a TUR to resolve her symptoms and to confirm the pathological diagnosis. The TUR was successfully completed, and the patient’s post-operative recovery was uneventful. Her LUTS were resolved a week after the operation.
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| Figure 2. Histopathological examination. a, b) Histopathological examination of the tumour 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 tumour was diagnosed as a leiomyoma. |
The pathological findings revealed the proliferation of spindle-shaped cells with eosinophilic cytoplasm and muscular and fibrous tissue with fibrous stroma. The nuclei of the cells were cigar-shaped and centrally located. No evidence of mitotic figures, coagulative T-cell necrosis or atypia was seen. Immunohistochemist