Introduction:

Intravesical recurrence after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC) is a relatively common event, with an incidence of approximately 20-50%. Several predictors and risk factors for intravesical recurrence have been identified. For example, specific tumor characteristics, such as multifocality, invasive pT stage, and necrosis, as well as treatment-specific predictors, such as laparoscopic approach and bladder cuff management, all were predictive of intravesical recurrence. Studies to date have been composed of mixed treatment cohorts - open, laparoscopic, and robotic. The objective of this study is to describe risk factors for intravesical recurrence after RNU for UTUC in a completely minimally invasive (robotic or laparoscopic) cohort.

Methods:

We performed a retrospective analysis of 521 patients with UTUC without prior or concurrent bladder cancer who underwent robotic or laparoscopic RNU. Patients were selected from an international cohort of 18 institutions across the United States, Europe, and Asia. Univariate (t-test, x², Fisher’s exact) and multivariate Cox regression models were used to identify risk factors for bladder recurrence.

Results:

Of the 870 patients that underwent RNU, 521 were included in this analysis after excluding patients with concomitant or previous bladder cancer. A total of 419 (80.4%) patients underwent robotic approach, 91(17.5%) laparoscopic, and 11 (2.1%) combined robotic and laparoscopic. Overall, 400 (76.8%) patients had no intravesical recurrence vs. 121 (23.2%) patients that did develop intravesical recurrence. The average time to recurrence was 14 months. Of the patients that underwent a diagnostic ureteroscopic biopsy, 27% had a recurrence compared to 17% who did not undergo biopsy (p=0.03). Biopsy prior to definitive therapy doubled the risk of intravesical recurrence [HR 2.21, CI 1.16-4.22; p=0.02). Among different techniques of bladder cuff management, excision and Hem-o-lok closure were both protective against intravesical recurrence [HR 0.113, CI 0.137-0.937; p=0.04, HR 0.086, CI 0.008-0.889; p=0.04, respectively]. A laparoscopic approach reduced the risk of intravesical recurrence compared to a robotic approach [HR 0.44, CI 0.218-0.887; p=0.02].

Conclusion:

This is the first multi-institutional, international study analyzing a fully minimally invasive cohort. On multivariate analysis, a pre-operative ureteroscopic biopsy and robotic approach were associated with an increased risk for intravesical recurrence. Bladder cuff management via excision or Hem-o-lok closure reduced the risk of recurrence. Intravesical recurrence after RNU for UTUC is a common event, and identifying and mitigating risk factors is critical for oncologic management.

Funding: N/A