[Ureteral polyp: a difficult case to make a differential diagnosis with ureteral tumor]

We report a case of primary fibroepithelial polyp of the left ureter. The patient was a 34-year-old-man, complaining of left flank pain. An excretory urogram and retrograde pyelogram revealed left hydronephrosis and filling defect of the middle third of ureter. It was difficult to make a differential diagnosis with ureteral tumor. A frozen section revealed no malignancy and we performed partial ureterectomy and end-to-end anastomosis. We discussed the clinical features of adult primary ureteral polyp reported in the Japanese literature.