Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper
urinary tract and
renal pelvis. Like colorectal
adenomas, these
neoplasms can transform into
adenocarcinoma. The preoperative
diagnosis is challenging due to their frequent
association with
hydronephrosis. Herein, we present the case of a
villous adenoma of the
renal pelvis in a 62-year-old man presenting with recurrent
urinary tract infection. The computed
tomography scan showed marked
hydronephrosis but no suspicious mass in the right
kidney. A laparoscopic right
nephrectomy was performed. Gross examination revealed a dilated
renal pelvis with an irregular exophytic lesion in the
renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with
villous adenoma morphology. Isolated
villous adenomas have a favorable
prognosis. However, the
pathologist should undertake a search for an invasive component.