A rare bladder tumour: A case presentation of primary low-grade leiomyosarcoma of the urinary bladder in a female patient

Abstract

Leiomyosarcoma is a mesenchymal tumour and rarely occurs as a primary bladder tumour. It is considered as a rare and aggressive tumour with a poor prognosis. To this date, there is no clear and precise therapeutic approach for the treatment of bladder leiomyosarcoma and little is known about the long term survival. The consensus in the current literature is that surgical intervention is the preferred initial treatment option and that prognosis is mainly determined by tumour differentiation. Organ-sparing surgery might be a feasible therapeutic option in selected patients.

1 Introduction

In this case report we describe the diagnosis and treatment of a 57 year old female patient with haematuria caused by a primary leiomyosarcoma of the urinary bladder. Written informed consent from the patient was obtained.

2 Case presentation

A 57-year-old female with no significant medical history was referred to our outpatient clinic due to gross haematuria and an abnormality in the urinary bladder on an abdominal ultrasound. The patient had no other urinary or general symptoms. The patient reported to have a history of smoking. During vaginal bimanual examination, a mobile mass was detected. Urinalysis revealed erythrocytes and no sign of cystitis, and urine cytology indicated The Paris System (TPS) 2. A cystoscopy was performed, revealing a large pedunculated solid mass located on the right posterior wall of the bladder ( Fig. 1 ). The aspect of the tumour on cystoscopy was not typical of urothelial carcinoma.

Subsequently, a Computed Tomography intravenous pyelogram (CT-IVP) of the abdomen was conducted, which showed a mass in the bladder with a maximum diameter of 3.8 × 2.4 cm with no extramural extension or signs of distant or regional metastases ( Fig. 2 ). It also showed a 8mm nephrolithiasis in the right upper pole calyx with a 6mm contrast opacification right beside it, possibly a small clot or a soft tissue configuration. A transurethral en-bloc resection of the mass in the bladder was performed followed by a diagnostic ureterorenoscopy on the right side which showed no tumour or clot in the right upper calyx.

Histopathological examination of the resected bladder mass showed cytonuclear atypia, significant polymorphism with increased mitotic activity, absence of necrosis, and positive staining for smooth muscle actin and desmin on immunohistochemistry ( Fig. 3 ). These findings led to the diagnosis of low-grade leiomyosarcoma. There was no malignancy found in the deep biopsy of the detrusor muscle at the tumour base. A repeat transurethral resection of the scar was performed. Histopathological analysis of the repeat resection showed no sign of malignancy.