Abstract

Cholesteatoma in the kidney and ureter are accumulations of waxy, gray flakes of keratin materials, secondary to squamous metaplasia of the transitional epithelium. Herein, we describe a case of cholesteatoma in the renal pelvis of a 69-year-old woman, and give a brief review of the literature. In the upper pole of the left kidney was a 6 cm cystic lesion filled with a thick, flaky, grayish, comified material. Microscopically, the cystic area showed calyceal and pelvic structures being replaced by keratinizing stratified squamous epithelium. The surrounding renal parenchyma was atrophic with features of chronic pyelonephritis.

• Keywords: Cholesteatoma;Kidney;Pelvis