Inflammatory myofibroblastic tumor of the bladder masquerading as eosinophilic cystitis: case report and review of the literature.

A 9-year-old boy presented with gross hematuria of 2 days duration. Cystoscopic evaluation revealed an anterior bladder mass. Pathology was consistent with eosinophilic cystitis, and a steroid regimen was initiated accordingly, but no improvement ensued. Concern for alternate malignant pathology led to open resection and the ultimate diagnosis of inflammatory myofibroblastic tumor of the bladder. Inflammatory myofibroblastic tumor is a rare tumor of the bladder in children and to our knowledge has not previously been associated with a misleading eosinophil-rich mucosal inflammatory response.