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Updated: May 19, 2026

Unilateral Ureteral Obstruction Model for Investigating Kidney Interstitial Fibrosis
Published on: April 25, 2025
Large ureteral fibroepithelial polyp lacking epithelium due to ischemic infarction
Lin Ye1, Lu-Jia Zhao, Feng Yue
1Department of Urology, Dalian Municipal Friendship Hospital, Dalian, People's Republic of China.
None:
We describe a woman with flank pain and hydronephrosis. Computed tomography (CT) urography and maximum intensity projection (MIP) reformatted images clearly showed that a long finger-like intraluminal filling defects mass in the left middle ureter. The pathologic biopsy by ureteroscopy revealed that the lesion mainly consists of benign fibrinoid necrosis. A large soft smooth, spindle-like, dark brown mass (approximately 13.5 cm in length) was identified in left middle ureter when open surgery was performed. The segment of the ureter part attached to the stalk of the polyp was excised, then a dismembered ureteroplasty was performed. Pathologic examination revealed that the total polyp was an ischemic infarction, characteristic of cellular swelling, tissue degeneration, fibrinoid necrosis, and thrombosis in its vessels. The surface of the polyp was hardly covered with urothelium, but fibroepithelial polyp was still diagnosed. There was no recurrence during the 3 years of follow-up.
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