Low-grade mucinous cystic tumor mimicking urinary bladder tumor: imaging-pathologic correlation.

Mucin-producing cystitis glandularis is a rare proliferative and metaplastic change of the bladder mucosa that produces large amounts of mucus, thus taking a pseudotumoral pattern and resulting in urinary tract obstruction. We report a case of florid mucin-producing cystitis glandularis mimicking bladder carcinoma in a 77-year-old man that was documented by computed tomography and magnetic resonance imaging. Computed tomography showed diffuse, circumferential, irregular, and lobulated thickening of the bladder wall suggestive of urinary bladder carcinoma. Magnetic resonance imaging showed findings consistent with mucinous content and suggested the correct diagnosis preoperatively.