Total endoscopic management of a patient with urinary bladder leiomyosarcoma presenting with dysuria: A case report

Abstract

The pathophysiology of bladder leiomyosarcoma, a rare disease with aggressive mesenchymal tumor, is not certain, but its main symptoms are hematuria, dysuria and abdominal pain. Cases described in the literature are few. This report describes a case of a leiomyosarcoma of the urinary bladder in a 49-year-old woman. After CT scanning revealed a heterogeneously enhanced 4-cm mass involving the bladder neck and anterior wall, further examinations detected no metastatic lesion. Cystoscopy and transurethral resection of bladder tumor (TURBT) were performed. The histopathological diagnosis was leiomyosarcoma. Postoperative period was uneventful. The patient experienced complete resolution of urologic symptoms. Repeat-TURBT was performed 70 days after first surgery. The patient has remained disease-free 18 months after surgery.

Introduction

Nonurothelial neoplasms of urinary bladder account for less than 5% of all bladder tumors. Particularly, leiomyosarcoma is a rare malignant mesenchymal tumor: of all urinary bladder malignancies, they are less than 1%. Urinary bladder leiomyosarcoma is a very rare disease with few case reports in the literature. No consensus exists for the standard treatment and prognosis of the tumor. Herein, we present the case of total endoscopic management of a patient with urinary bladder leiomyosarcoma presenting with dysuria.1, 2, 3, 4

Case report

A 49-year-old woman with medical history of hypertension and with a 12-month history of frequent urinary tract infections presented with progressive symptoms of dysuria. The patient had no history of radiotherapy or chemotherapy treatment. Urinary cytology was negative for urothelial malignant cells. Ultrasonography revealed a mass of considerable size occupying a large portion of the urinary bladder. Contrast-enhanced computed tomography (CT) scanning showed a heterogeneously enhanced 4 cm mass involving bladder neck and anterior wall. No enlarged lymph node was detected on pelvic and abdominal CT (Fig. 1). Cystoscopy and transurethral resection of bladder tumor (TURBT) were performed. Resected specimens were sent for histopathological examination. The 4.3 × 4.0 cm ulceroproliferative tumor filled the lumen of the urinary bladder. A cut section of the mass exhibited grayish-white whorly areas with necrosis and foci of calcification. Microscopically, the tumor was composed of a proliferation of interlacing fascicles of atypical spindle shaped cells, accompanied by bizarre nuclei (1–12/HPF).

Fig. 1.

CT scan showing heterogeneously enhanced 4 cm mass involving the bladder neck and anterior wall. No enlarged lymph node was detected.

Mitotic figures were observed frequently (3/HPF in hot spot). Immunohistochemically, the tumor cells were positive for alpha-SMA and desmin, focally positive for h-caldesmon and calponin, but negative for myogenin, S-100 protein, p40 and CK903, CDK4, and MDM2. The final diagnosis was leiomyosarcoma (Fig. 2, Fig. 3). The surgical margins were positive. The postoperative period was uneventful. The patient experienced complete resolution of urologic symptoms. Repeat-TURBT was performed after 70 days from first surgery. The surgical margins were negative. The follow-up CT scan 18 months after surgery showed no sign of recurrence. Cystoscopy then showed that the bladder was tumor free. The patient is living uneventfully, but declined to engage in further follow-up.

Fig. 2.

The tumor was composed of a proliferation of interlacing fascicles of atypical spindle shaped cells, accompanied by bizarre nuclei (1–12/HPF). Mitotic figures were frequently observed (3/HPF in hot spot).

Fig. 3.

Tumor cells were positive for alpha-SMA.

Discussion

Mesenchymal tumors of the bladder account for 0.1% in adults. Bladder leiomyosarcoma is the most prevalent. Fewer than 200 cases of this tumor have been reported in the literature.¹ Most malignant bladder tumors are of epithelial origin. Sarcomas account for less than 1% of malignant bladder tumors. Leiomyosarcoma, arising from urinary bladder smooth muscle, was first reported by Rowland and Eble.² Gross hematuria, the most commonly presenting symptom, accounts for more than 80% of cases. Strong evidence exists that the incidence of leiomyosarcomas is increased in patients receiving pelvic radiotherapy or systemic chemotherapy such as cyclophosphamide³

Because it is a rare tumor, a lack of consensus exists related to its pathophysiology, treatment, and prognosis. The treatment should be adapted to each case. Microscopically infiltrative interlacing fascicles of spindle cells are noted. Microscopic grading is based on nuclear atypia, mitotic activity, and tumor necrosis. Immunohistochemically, vimentin, muscle-specific actin, and (often) desmin are positive. Epithelial markers and ALK-1 are usually negative.²

More than 60% of leiomyosarcoma patients develop recurrent or metastatic disease. The lungs, liver, bone, and brain are the most common sites of metastases.⁴ Reportedly, it has a specific five-year survival rate of 62%, and a recurrence rate of 34% in 38 months. No general consensus exists for treatment, but it is regarded as a highly aggressive entity that requires an aggressive surgical extirpation with wide margins. The best prognostic factor is the presence of tumor-free margins.³ In addition, the tumor size (<5 cm tumor diameter), the degree of tissue involvement, and the free margins are apparently good parameters to evaluate the prognosis.¹ Radical cystectomy with ample surgical margins is apparently the best treatment course. Minimally invasive treatment such as transurethral resection and adjuvant chemoradiation is an alternative for patients refusing a radical treatment. It must be used for patients with small tumors. Partial cystectomy with sole resection of the mass should be regarded as a palliative treatment: it is only possible with certain tumor locations.³

Although bladder sarcomas were once thought to have a grim prognosis, some patients are apparently able to achieve long-term survival, especially if an adequate surgical approach is deployed as the primary treatment. One report of the relevant literature describes the case of a 31-year-old woman with a 4 cm diameter leiomyosarcoma on the left wall of the bladder, treated by partial cystectomy. That report indicated that although bladder leiomyosarcoma has always been regarded as a highly aggressive tumor, partial surgery is now considered a reliable option because it preserves function and decreases aggressiveness.⁴

In our case, we opted for a minimally invasive endoscopic approach to treat this tumor. We decided to perform a TUR of leiomyosarcoma because the patient had a small mass, with 4 cm diameter. Moreover, no enlarged lymph node was detected on pelvic or abdominal CT. Fortunately, during 18 months of follow-up, the patient showed no sign of tumor recurrence.

Conclusion

Leiomyosarcomas of the bladder have always been regarded as a highly aggressive disease with poor prognosis. Early detection and surgery for urinary bladder leiomyosarcoma can improve the treatment efficacy considerably. We presented a case of a leiomyosarcoma that was treated primarily with minimally invasive surgery. Although radical cystectomy is still apparently the best choice of treatment, transurethral resection of bladder tumor constitutes a reliable option to treat smaller leiomyosarcomas (<5 cm tumor diameter) because it can provide similar therapeutic efficacy and better quality of life to the patient.

Financial support and sponsorship

None.

Conflicts of interest

The authors have no conflict of interest, financial or otherwise, in relation to this study.