Endovesical leiomyoma of bladder treated by enucleation: A case report.

Introduction

Leiomyomas are mesenchymatous tumors considerated as benign. Bladder is the most frequent location and it represents 30% of benign bladder tumors. The diagnosis is histological. The prognosis is excellent after treatment.

Case report

A 43-year-old female patient, with no medical or surgical history, presented with pelvic pain of two months duration, without fever or any associated urinary signs. Her examination revealed a sensible pelvis, and on vaginal examination there was a homogeneous mass depending on the anterior vaginal wall. The cervix was clinically normal. Biology revealed a normal renal function and a sterile urine. Ultrasonography of the bladder showed a trigonal vascularized mass measuring 43 × 37 mm (Fig. 1). On MRI there was a tissular subserous mass protruding into the bladder (Fig. 2). A transurethral biopsy and histological examination concluded to bladder leiomyoma. A digital intravesical enucleation of the mass was performed, using the median suprapubic approach. Final histological examination concluded to bladder leiomyoma (Fig. 3). After 14 months of clinical, radiological and endoscopic check-up, there was no functional complaint or any sign of reoccurrence.

Fig. 1

An exophytic mass in the bladder trigone measuring 43 × 37 mm vascularized to the doppler.

Fig. 2

MRI there was a tissular subserous mass protruding into the bladder.

Fig. 3

The histology shows a mesenchymal proliferation of smooth muscular nature, these fibers are arranged in intersecting bundles, the interstitial tissue is richly vascularized.

Discussion

Urinary tract leiomyomas are rare, as they represent less than 5% of urinary tract tumors.1, 2, 3 They may be found at any level of urinary tract. Vesical location remains the most frequent with 30% of cases. Bladder leiomyomas affect children but also adults with a sex ratio of 30%. Bladder Leiomyoma is localized on the trigone in 2/3 of cases and more rarely on lateral bladder walls.2, 3 In most cases, the tumor origins from the smooth muscle bundles (60%) and has more rarely an extravesical (30%) or intramural (10%) location. The clinical symptoms depend on the anatomic location. Intravesical tumors frequently present with urinary signs such as dysuria, urinary infections and more rarely hematuria. Extravesical or intramural tumors present with few late symptoms, due to neighboring organs compression. Pelvic ultrasonography shows a solid, lobulated, homogeneous and echogenic mass covered by an intact mucosa, more echogenic than the tumor.2, 3 Pelvic CT shows a tissular homogeneous mass, mostly localized on the trigone and the bladder floor, with a mass effect on the adjacent organs without signs of invasion or infiltration.2, 3 MRI remains the gold standard for the diagnosis and shows a homogeneous mass having low intensity both on T1 and T2, and enhancing homogeneously after injecting gadolinium contrast medium. Differential diagnosis may include other bladder tumors such as hemangioma, pheochromocytoma and especially bladder leiomyosarcoma. The treatment depends on the location and the size of the tumor. With small endovesical tumors, endoscopic resection is preferentially performed. Meanwhile, complete removal of the tumor should be ensured. In other cases, surgical enucleation of the tumor is performed, as it is mostly accessible to dissection. When the tumor is completely removed, the prognosis is excellent with no reoccurrence reported.4, 5 On histological examination, the leiomyoma appears as a white-greyish-coloured, well-circumscribed tumor, composed of spindle cells and fibers arranged in fascicles with no evidence of atypia or mitosis, and covered with intact mucosa rarely edematous or eroded. The prognosis is excellent after resection.

Conclusion

Although rare, bladder leiomyoma is the most common benign bladder tumor. It may increase in size and cause ureteral or cervical obstruction. It can also present with urinary signs, especially hematuria. MRI remains the gold standard for the diagnosis and the study of connections with neighboring organs. However, this tumor does not have any specific radiological characteristics outside its regular contours. Diagnosis can only be made by endoscopic biopsy. Its treatment is conservative. The prognosis is excellent.

Conflicts of interest

The authors declare that there are no conflicts of interest regarding the publication of this article.