Kidney sparing surgery in upper tract urothelial carcinoma: paradigm change in surgical treatment for ureter cancer.

Purpose: To extend the indications of kidney-sparing surgery (KSS) for ureter cancer by comparing the oncological outcomes between patients with upper tract urothelial carcinoma (UTUC) who underwent radical nephroureterectomy (RNU) or KSS.

Methods: We retrospectively reviewed 708 patients with UTUC who underwent RNU (N = 646) or KSS (N = 62) between 2011 and 2019 to analyze the oncologic outcomes and prognostic factors. Subgroup analyses were performed for patients with unifocal ureteral urothelial carcinoma (UC).

Results: No significant difference was observed in the overall survival (OS) or cancer-specific survival (CSS) between RNU and KSS (distal ureterectomy with reimplantation (N = 33), ureterectomy with ileal ureter (N = 14), ureteroscopic tumor resection (N = 10), and ureterectomy with ureteroureterostomy (N = 5)). Among 269 (38.0%) patients with unifocal ureteral UC, 219 and 50 patients underwent RNU and KSS, respectively. OS and CSS were not significantly different between these two groups. Pathologic stage was a significant risk factor in multivariate analysis (hazard ratio = 2.621; p = 0.000). Among 646 RNU patients, 219 (33.9%) had unifocal ureteral UC, 40 (18.3%) with low-grade tumors. Among these, 13 (5.9%) patients with unifocal, low-grade and small (< 2 cm) tumors received nephroureterectomy.

Conclusion: Kidney-sparing surgery should be regarded as an important alternative to RNU for patients with unifocal ureteral UC thought to have noninvasive disease to preserve renal function and reduce overtreatment.