[Pseudosarcomatous fibromyxoid tumor of the urinary bladder: a case report].

A 41-year-old man was referred to our clinic for gross hematuria. Cystoscopy revealed a 6 x 5 x 5 cm wide-based tumor located at the dome of the bladder. Pathological diagnosis of the biopsy was pseudosarcomatous fibromyxoid tumor. Microscopically this tumor was composed of spindle cells and myxoid stroma, and immunohistochemical and ultrastructural studies showed benign characteristics of this tumor. Therefore partial cystectomy was performed. It is important to recognize the histological characteristics of this essentially benign condition so that total cystectomy can be avoided.