Effects of previous or synchronous non-muscle invasive bladder cancer on clinical results after radical nephroureterectomy for upper tract urothelial carcinoma: A multi-institutional study

Purpose: To evaluate the effects of the presence of previous or synchronous non-muscle invasive bladder cancer (NMIBC) on the oncologic outcomes of radical nephroureterectomy in patients with upper tract urothelial carcinoma (UTUC). Materials and Methods: In total, 505 patients with UTUC were enrolled from four different institutions. The clinicopathologic parameters of patients with and without previous or synchronous NMIBC were compared, and Kaplan-Meier estimates and multivariate Cox regression analyses were performed. Results: The median follow-up period was 38.4 months. In all, 408 patients had primary UTUC, 45 (8.9%) had a history of NMIBC, 59 (11.7%) had concomitant bladder cancer, and seven (1.4%) had experienced both. Tumors in patients with associated NMIBC were more commonly multifocal (P =.001) and associated with surgical margin positivity (P =.001). Kaplan-Meier estimates revealed that previous or synchronous NMIBC was significantly associated with bladder recurrence (P <.001) and locoregional recurrence/distant metastasis (P =.008). A multivariate Cox regression model identified previous or synchronous NMIBC as an independent predictor of bladder recurrence (P <.001). However, the presence of previous or synchronous NMIBC was not a prognostic indicator of locoregional recurrence/distant metastasis. Conclusion: In patients with UTUC, previous or synchronous NMIBC was significantly associated with an increased risk of cancer recurrences in the bladder after radical nephroureterectomy. The present findings suggest that a close monitoring should be required for the patients with previous or concomitant NMIBC.