Preoperative Renal Impairment and Oncological Outcomes After Radical Cystectomy: A Multicenter Cohort Study

Preoperative renal impairment is common among patients undergoing radical cystectomy (RC) for bladder cancer and has been associated with adverse outcomes. However, whether this association reflects an independent prognostic effect of kidney function remains uncertain.

To evaluate the association between preoperative kidney function and recurrence-free survival (RFS) and overall survival (OS) using 2021 CKD-EPI estimated glomerular filtration rate (eGFR) and measured 24-hour creatinine clearance (mCrCl).

We retrospectively analyzed 396 patients who underwent RC for muscle-invasive bladder cancer. Preoperative renal impairment was defined as eGFR < 60 mL/min/1.73 m² or mCrCl < 60 mL/min. Associations with RFS and OS were assessed using Kaplan-Meier analyses and Cox regression models with sequential adjustment for age and sex and for pathological and treatment-related characteristics. Kidney function was additionally analyzed continuously and using restricted cubic spline models.

Renal impairment was present in 63/396 patients (15.9%) by eGFR and in 51/318 evaluable patients (16.0%) by mCrCl. Five-year RFS and OS were significantly lower in patients with impaired kidney function by both measures. For eGFR < 60 mL/min/1.73 m², age- and sex-adjusted hazard ratios (HRs) were 2.37 (95% confidence interval [CI], 1.52-3.69; P < .001) for RFS and 1.91 (95% CI, 1.17-3.15; P = .010) for OS. After full adjustment for age, sex, pathological stage, nodal status, lymphovascular invasion, urinary diversion, and neoadjuvant chemotherapy, these associations were attenuated to HR 1.29 (95% CI, 0.79-2.10; P = .312) for RFS and HR 1.36 (95% CI, 0.80-2.30; P = .259) for OS. For mCrCl < 60 mL/min, age- and sex-adjusted associations were not statistically significant, and fully adjusted HRs were 0.95 (95% CI, 0.56-1.61; P = .843) for RFS and 0.95 (95% CI, 0.53-1.72; P = .876) for OS. Continuous analyses showed a similar attenuation after full adjustment. Restricted cubic spline analyses suggested nonlinear associations, particularly for mCrCl, with substantial uncertainty at the extremes.

Preoperative renal impairment was associated with inferior unadjusted survival after RC, but this association was substantially attenuated after full adjustment, questioning its independent prognostic value.