The effect of radical nephroureterectomy (RNUx) on postoperative renal function in upper tract urothelial carcinoma (UTUC) patients, particularly regarding long-term renal impairment and oncological outcomes, has not been thoroughly examined.

We conducted a retrospective multicenter study of 785 patients who underwent RNUx for UTUC. Pre- and postoperative estimated glomerular filtration rates (eGFR) were assessed, and factors influencing significant postoperative eGFR decline were analyzed. The impact of comorbidities such as diabetes and hypertension on renal function decline at one year postoperatively was also investigated. Oncological outcomes, including non-urothelial tract recurrence-free survival (NUTRFS), cancer-specific survival (CSS), and overall survival (OS), were evaluated using Cox proportional hazard models.

The median preoperative eGFR was 54.7 mL/min/1.73 m², and the median postoperative eGFR was 40.6 mL/min/1.73 m². Only 5.1% of patients retained a postoperative eGFR ≥ 60 mL/min/1.73 m², compared to 35.9% preoperatively. The median eGFR decline post-surgery was 26.8%. Preoperative eGFR < 60 mL/min/1.73 m² was associated with lower odds of a ≥ 25% decline in eGFR. Comorbidities significantly impacted renal function at one year (p = 0.048). Preoperative chronic kidney disease was linked to worse outcomes.

Patients with UTUC experience significant renal impairment post-RNUx. Tailored perioperative strategies are needed, especially for those with preexisting renal impairment.