Cholesteatoma of the renal pelvis: a case with long-term followup.

We report a case of cholesteatoma of the renal pelvis with a 56-year followup. Quiescence of the disease with remission of symptoms, stabilization of the lesion and absence of further anatomical change was related temporally to treatment with vitamin A. The disease in our patient was idiopathic and no causative or predisposing factors were demonstrated.