Background: Contralateral recurrence of upper-tract urothelial carcinoma (UTUC) presents a clinical challenge, with limited evidence regarding optimal surgical management. Objective: To compare oncological outcomes among patients with contralateral UTUC recurrence managed by second nephroureterectomy (NUR) or nephron-sparing surgery (NSS), relative to those undergoing primary NUR. Design: A multicentre retrospective cohort study. Methods: In this multicentre retrospective cohort, 3159 patients diagnosed with UTUC between 2018 and 2024 in the Taiwanese UTUC Registry were analysed. Patients undergoing curative-intent surgery were grouped as follows: unilateral UTUC treated with primary NUR; contralateral recurrence treated with a second NUR; and contralateral recurrence managed with nephron-sparing surgery (NSS; segmental ureterectomy or endoscopic ablation). NUR was performed via open, laparoscopic, or robotic-assisted approaches. Outcomes included overall survival (OS), cancer-specific survival (CSS) and bladder recurrence-free survival (BRFS). Propensity score-based overlap weighting adjusted for baseline differences. Results: After adjustment, both second NUR and NSS achieved OS, CSS, and BRFS comparable to primary NUR. Tumour biology, including stage, lymphovascular invasion and multifocality, exerted greater prognostic impact than contralateral recurrence status or surgical modality. While the rarity of contralateral recurrence limited statistical power, particularly for CSS and in the NSS subgroup, the consistency of effect estimates supports the robustness of the observed trends. Conclusion: In this multicentre real-world cohort, second NUR and NSS for contralateral UTUC recurrence demonstrated broadly comparable survival outcomes to primary NUR, though the limited number of NSS cases and corresponding statistical power preclude firm conclusions.
Kao et al. (Sun,) studied this question.