A rare association in a patient with non-muscle invasive bladder cancer: ureteral fibroepithelial polyp and ipsilateral renal cell carcinoma: a case report.

<bold>Background: </bold>Fibroepithelial polyps located in the ureter constitute 2-6% of all benign tumors in the urinary system. Distinguishing these lesions from transitional cell carcinoma is essential to avoid unnecessary nephroureterectomy.<bold>Case Presentation: </bold>A 59-year-old asymptomatic caucasian male patient was enrolled in follow-up for Ta low-grade transitional cell bladder cancer 4 years ago in our clinic. A suspicious, solid, contrast-enhancing mass 15 × 9 mm in diameter in the anteromedial mid-section of the left kidney, which was causing minimal washout and largely located in the parenchyma, was reported as renal cell carcinoma on computed tomography during routine controls. In the excretory phase, soft-tissue densities of approximately 30 mm in length, which were located in the distal part of the left ureter at a distance of 40 mm from the ureterovesical junction, extending towards the lumen suggested a urethral carcinoma. Urothelial lesion was reported as fibroepithelial polyp after histopathological examination. Partial nephrectomy for the mass, which was reported as renal cell carcinoma in the left kidney, was performed in the first postoperative month. Histopathological examination revealed Fuhrman grade 1 papillary type renal cell carcinoma. No recurrence was observed in the first year after treatment.<bold>Conclusions: </bold>Although our patient had a bladder transitional cell carcinoma and a suspicious renal cell carcinoma mass of 15 mm in the ipsilateral kidney, the patient was safeguarded from unnecessary nephroureterectomy early on by cross-sectional and endoscopic imaging of the ureter. [ABSTRACT FROM AUTHOR]