Outcome and Impact of Diagnostic Ureteroscopy in Clinically Suspected Upper Urinary Tract Carcinoma in Situ.

Objectives: To clarify disease behavior and oncological outcomes as well as the need for ureteroscopy (URS) implementation in patients with clinically suspected upper tract carcinoma in situ (UT-CIS). Patients and Methods: In this multi-institutional study, we retrospectively analyzed patients who met three criteria for clinically suspected UT-CIS between 2008 and 2018: positive high-grade cytology from the upper tract, absence of a solid upper tract lesion on imaging, and negative bladder biopsy. Patients who underwent URS were compared with those who did not. Kaplan-Meier curve was used to assess the natural history of treated UT-CIS and the prognostic impact of URS. Results: In total, 48 patients with clinically suspected UT-CIS were analyzed, of whom 27 (57%) had a previous history of urothelial carcinoma. Of 28 (58%) patients who underwent URS, pathologically confirmed UT-CIS and UT-non-CIS were detected in 7 (25%) and 6 (21%), respectively. As initial treatment, 23 (48%) patients received upper tract bacillus Calmette-Guérin, while 21 (44%) underwent radical nephroureterectomy (RNU). During a median follow-up of 44.8 months, the most common site that suffered recurrence and progression was the bladder (40% and 17%), followed by the affected (15% and 6%) and contralateral (8% and 4%) upper tract, respectively. Three-year overall, cancer-specific, upper tract-specific, progression-free (PFS), and recurrence-free survival estimates were 88.2%, 94.8%, 100%, 80.8%, and 52.4%, respectively. Survival outcomes were comparable regardless of URS implementation, with the exception of PFS. However, URS implementation resulted in an earlier transition to surgical intervention in 11% and avoided unnecessary RNU in 11%. Conclusions: UT-CIS is a pan-urothelial disease and frequently shows metachronous recurrence and progression in any part of the urinary tract, necessitating long-term, meticulous follow-up. Despite the lack of a statistical difference between patients with and without URS, we found that a non-negligible number of patients benefited from URS implementation.