Rare pseudotumors of the urinary bladder in childhood.

We report two cases of inflammatory pseudotumors of the urinary bladder, one case of a chronic granulomatous pseudotumor (CGT) and one case of a pseudosarcomatous myofibroblastic (fibromyxoid) tumor (PMT). Both tumors resembled malignancies such as rhabdomyosarcomas regarding clinical appearance and imaging findings and represent rare urinary bladder tumors. The imaging findings on unenhanced and contrast-enhanced MRI as well as histological specimen are presented. Final diagnosis was made following elective surgery. Differential diagnosis of urinary bladder tumors as well as the imaging findings of these clinically comparable cases are discussed. Awareness of these benign lesions may prevent patients from inappropriate therapies such as chemotherapy or radiation therapy.