Primary malignant mesenchymoma of bladder: Case report and review of the literature.

RATIONALE

Malignant mesenchymoma (MM) is defined as a heterogeneous malignant soft tissue tumor that consists of 2 or more distinctly different mesenchymal components in addition to fibrosarcomatous elements. Bladder MM was rarely reported in the literature and there are only 5 cases of primary bladder MM documented in English literature to date.

PATIENT CONCERNS

A 58-year-old male complained of difficulty in urination and intermittent gross hematuria for 3 months. Doppler ultrasound scan revealed an avascular and homogeneous hypoechoic mass measured 6.5 × 9 cm in the bladder. Computed tomography showed a homogeneous solid mass in the bladder.

DIAGNOSES

Pathology revealed spindle-shaped tumor and proliferation of poorly differentiated immature mesenchymal cells rich in eosinophilic cytoplasm with hyperchromatic sticklike nuclei. Immunohistochemical examinations were positive for CD117.

INTERVENTIONS

The patient was diagnosed with presence of bladder tumor and underwent radical cystectomy; the optimal treatment strategy was reviewed and discussed.

OUTCOMES

There was no recurrence or metastasis during a 16-month follow-up.

LESSONS

Our case study demonstrated bladder MM with a relatively indolent clinical course. A multidisciplinary approach including surgery, radiotherapy, and chemotherapy may be useful. Radical resection is the most important determinant of clinical outcome. Generally, the clinical outcome and prognosis of mesenchymoma are favorable.