[Fibroepithelial polyp of the kidney pelvis].

Benign fibroepithelial polyps of the renal pelvis are rare. Because of suspected malignancy in imaging procedures an ureteronephrectomy was carried out in the reported case. Histology, however, yielded no evidence of malignancy. The diagnosis of benign fibroepithelial polyp was entertained. It remains an open question whether the pathologic changes represent a hamartoma or a reactive postinflammatory process, revealing primitive myxoid stroma within the polypous portion and increasing fibrosis with diffuse submucosal involvement of the ureteral basis.