Abstract

Cholesteatoma in the urinary system is a rarely seen benign condition. Rosina firstly defined this condition  in the year  1953. Histopathologically it is characterized with keratinization, and  squamous metaplasia of urothelial epithelium associated with desquamation of keratinized layers. Flank pain is the most common symptom that is caused by  elimination of keratinous material. In our case we will discuss cholesteatoma developed in an ectopic kidney which has not been described in the literature before.