Mucinous Cystadenoma Arising From Renal Pelvis

Received July 2007 Accepted April 2008 INTRODUCTION Epithelial tumors originating from the renal pelvis are uncommon, and adenocarcinomas account for less than 1% of malignancies which arise from renal pelvic epithelium.(1) Primary mucinous epithelial tumors occurring in the kidney are presumed to originate from the multipotential renal pelvic epithelium. Most reported cases are malignant.(2) Only isolated cases have been reported where the epithelial lining of the tumor was benign.(3) We report 2 cases of mucinous cystadenoma arising from the renal pelvis and discuss the histogenesis of this rare lesion.