[Fibromyxoid tumor of the bladder: report of 3 cases]

Fibromyxoid tumours are rare inflammatory bladder tumours. These benign tumours are responsible for minimal symptoms. The diagnosis is based on histological examination showing spindle cells infiltrating the detrusor associated with more or less abundant inflammatory infiltrates. It is important to demonstrate the myofibroblastic nature of these cells, which constantly express specific muscle actin and smooth muscle actin on immunohistochemistry. The differential diagnoses are high-grade sarcomatoid spindle cell urothelial carcinoma, leiomyosarcoma and embryonal rhabdomyosarcoma in children. Treatment is surgical, comprising complete endoscopic resection or partial or total cystectomy. The authors report 3 new cases of fibromyxoid tumours treated conservatively by complete endoscopic resection or partial cystectomy. No recurrence was observed. The authors present a review of the literature and a discussion of the differential diagnoses.