Clinical features of patients with nonmalignant upper tract lesions mimicking urothelial cancer

Purpose: The purpose is to evaluate the incidence and clinical features of patients who have undergone nephroureterectomy with nonmalignant upper tract lesions presumed to be urothelial carcinoma from images in Taiwan. Materials and Methods: Between October 2004 and October 2015, our institute had 350 patients who underwent retroperitoneoscopic nephroureterectomy for possible upper urinary tract urothelial carcinoma without a routine diagnostic ureteroscopy (URS) or ureteroscopic biopsy. Trauma, urolithiasis, or infection were excluded. We collected imaging findings; urine cytology results; renal function status; previous urothelial history; and the final pathology results. Twenty-three (6.6%) patients had nonmalignant benign lesions found from pathology. Results: The 23 patients comprised nine men and fourteen women. Most patients were middle-aged. Initial symptoms included gross hematuria, hydronephrosis, and flank pain. From self-voided urine cytology, the most common result was atypical cells. The number of patients was equal in the end-stage renal disease (ESRD) plus postkidney transplantation group and the non-ESRD group. In addition, we divided patients into two groups according to lesioned kidney function status: Nonfunctional kidney (NFK) or functional kidney (FK). The most common pathologic feature found in the NFK group was atrophic kidneys. On the other hand, the most common diagnosis in the FK group was pyelonephritis. Conclusion: Nonmalignant pathologic lesions were detected in 23 patients who had undergone retroperitoneoscopic nephroureterectomy without preoperative diagnostic URS for upper tract lesions. Self-voided urine cytology provided limited information for diagnosis in this group. For the almost 75% of patients with NFK, nephroureterectomy may be a feasible diagnostic and therapeutic method.