Objective  To investigate whether ureteroscopic biopsy was necessary for patients with upper tract urothelial carcinoma (UTUC), diagnosed by computed tomography urography (CTU), before radical nephroureterectomy (RNU).

  Methods  We conducted a retrospective study of 73 patients who were diagnosed with UTUC after surgery in The First Affiliated Hospital of Zhengzhou University from September 2011 to May 2020. We compared the UTUC positive rate between CTU and ureteroscopic biopsy. In addition, the discordance in grading between ureteroscopic biopsy and surgical pathology findings was analyzed.

  Results  Seventy of the 73 patients underwent CTU, and all of them showed abnormalities. The positive rate of diagnosis was 88.6% (62/70), and all tumors were pathologically confirmed as urothelial tumors. Sixty-one patients underwent ureteroscopic biopsy, and the positive rate of diagnosis was 91.8% (56/61). At biopsy, 39.3%(24/61) of patients had clinically high-grade tumors while 52.5%(32/61) had clinically low-grade tumors. At the final pathology, 77.1%(47/61) of patients had pathologically high-grade tumors while 22.9% (14/61) had pathologically low-grade tumors. Among the cases involving clinically low-grade tumors on biopsy, tumor grade was upgraded after surgery in 56.2% (18/32) of cases. There was no difference in the positive rate of UTUC diagnose between CTU and ureteroscopic biopsy (P=0.537).

  Conclusion  There is a significant risk of up-grading in patients with clinically low-grade tumors on biopsy. Preoperative ureteroscopic biopsy is not recommended for UTUC patients who have been diagnosed based on CTU findings.