LAUSR

Cystic renal lesions are extremely common. The major clinical concern is differentiating simple renal cysts from complex cysts to assess the risk of malignancy. The Bosniak classification of renal cystic tumors is employed to distinguish benign cysts from potential malignant cysts. Benign renal tumors can be rarely encountered in Bosniak type 4 cysts. Herein, we report a case of 56-year-old female with a single right mediorenal solid-cystic mass classified bosniak 4. An open surgery was planned: There was a 2-cm-sized cystic tumor, mediorenal, in contact with the hilum. A lumpectomy was performed. Anatomopathological examination revealed a cystic oncocytoma.