Introduction

We previously reported on the long-term recovery of renal function after radical nephrectomy (RN) (J Urol 2011, Int J Urol 2016). Atypically, some patients experience longitudinal decline in post-nephrectomy renal function, and a few eventually develop end-stage renal disease (ESRD). A >30% decrease in estimated glomerular filtration rate (eGFR) has been shown to be a risk factor for ESRD and all-cause mortality in chronic kidney disease (CKD) patients. Here, we investigated the incidence and risk factors of a >30% eGFR decline from the postoperative baseline in patients undergoing radical nephrectomy (RN).

Methods

This multicenter study included 894 patients who had undergone RN between 1994 and 2014. Patients with bilateral renal tumors, metastases, preoperative ESRD, and follow-up <1 year were excluded. The primary endpoint was a >30% eGFR decrease from the postoperative baseline, which was defined as eGFR at 1 month after RN. We identified the preoperative risk factors for a >30% eGFR decrease using the Cox proportional hazard model. A risk-stratification model incorporating independent risk factors was then generated.

Results

The median age, preoperative eGFR, and postoperative baseline eGFR of the 894 patients (593 men, 301 women) were 65 years, 70.5, and 45.1 ml/min/1.73 m², respectively. Of these, 235, 351, 126, and 131 patients had preoperative CKD defined as eGFR <60 ml/min/1.73 m², hypertension (HT), diabetes mellitus, and cardiovascular disease, respectively. During the median follow-up of 48 months, a >30% eGFR decrease from the postoperative baseline was observed in 47 patients (5.3%). ESRD requiring dialysis developed in 10 of the 47 patients. Multivariate analysis revealed that preoperative CKD and HT were independent risk factors for a >30% eGFR decrease. Five-year >30% eGFR decrease-free survival rates were 98%, 94%, and 84% in patients with 0, 1, and 2 risk factors, respectively (p < 0.001, Figure). Of the 10 patients who developed ESRD, 8 had both risk factors and the remaining 2 had 1 risk factor.

Conclusions

Approximately 5% of patients undergoing RN experienced a >30% eGFR decrease from the postoperative baseline, and one-fifth of these patients eventually developed ESRD. Preoperative CKD and HT were the risk factors for a >30% decline in eGFR.

Funding

None