Intra renal epidermal cyst simulating a renal tumor: A case report

Abstract

Epidermoid cyst is an unusual and very rarely described lesion in the kidney. We report the case of a 45-year-old woman with no known pathological history who presented with right flank pain accompanied by macroscopic hematuria. The physical examination was unremarkable. The CT scan evoked a malignant tumor in front of a right renal mass with irregular contours. The patient underwent a total right nephrectomy. The nephrectomy specimen received for pathological examination showed macroscopically an encapsulated cystic mass of 4 cm long axis. The cyst lumen was occupied by solid brownish tissue debris. Histologically, the cystic wall was lined by a keratinizing squamous epithelium with accumulation of keratin lamellae in the cystic lumen. Anatomopathological examination concluded to the diagnosis of renal epidermoid cyst.

Keywords: Epidermoid cyst; Histopathology; Renal.

Fig. 1

CT image showing right renal lesion.

Fig. 2

Macroscopic section of the kidney showing an encapsulated cystic lesion occupied by brownish friable solid tissue.

Fig. 3A

microscopic image G100, HE stain, showing on the right a cystic wall lined by a keratinizing squamous epithelium. On the left there is a renal parenchyma without atypia separated from the cystic wall by a fibrous tissue.

Fig. 3B

Microscopic image, G200, HE stain, showing on the left the cystic wall lined by a keratinizing pluristratified squamous epithelium separated from the renal tissue on the right by a fibrous tissue.