Prediction of significant estimated glomerular filtration rate decline after renal unit removal to aid in the clinical choice between radical and partial nephrectomy in patients with a renal mass and normal renal function

Abstract

ObjectivesTo develop a clinically applicable predictive model to quantitate the risk of estimated glomerular filtration rate (eGFR) decline to ≤45 mL/min/1.73 m 2 after radical nephrectomy (RN) to better inform decisions between RN and partial nephrectomy (PN). Patients and MethodsOur prospectively maintained kidney cancer registry was reviewed for patients with a preoperative eGFR >60 mL/min/ 1.73 m 2 who underwent RN for a localized renal mass. New baseline renal function was indexed. We used multivariable logistic regression to develop a predictive nomogram and evaluated it using receiver-operating characteristic (ROC) analysis. Decision-curve analysis was used to assess the net clinical benefit. ResultsA total of 668 patients met the inclusion criteria, of whom 183 (27%) experienced a decline in eGFR to ≤45 mL/min/ 1.73 m 2 . On multivariable analysis, increasing age (P = 0.001), female gender (P < 0.001), and increasing preoperative creatinine level (P < 0.001) were associated with functional decline. We constructed a predictive nomogram that included these variables in addition to comorbidities with a known association with kidney disease, but found that a simplified model excluding comorbidities was equally robust (cross-validated area under the ROC curve was 0.78). Decision-curve analysis showed the net clinical benefit at probabilities >~11%. ConclusionsThe decision to perform RN vs PN is multifaceted. We have provided a simple quantitative tool to help identify patients at risk of a postoperative eGFR of ≤45 mL/min/1.73 m 2 , who may be stronger candidates for nephron preservation.

Robust Association between Acute Kidney Injury after Radical Nephrectomy and Long-term Renal Function

“…However, these studies simply compared renal functional outcomes between radical and partial nephrectomy and cannot confirm the causal relationship between radical nephrectomy and new-onset CKD. A recent study constructed a simplified nomogram that predicts postoperative renal functional decline after nephrectomy and could help determine candidates for partial nephrectomy [24]. For stage 1 renal tumors, oncologic outcomes were not different between partial and radical nephrectomy [25,26].…”

Acute Kidney Injury Adjusted for Parenchymal Mass Reduction and Long-Term Renal Function after Partial Nephrectomy

“…Nevertheless, using the conventional diagnostic criteria of AKI, the incidence of AKI after partial nephrectomy was reported to be as high as 39%–54% [1,2]. Renal functional decline after partial nephrectomy is due to incomplete recovery of the remaining kidney from ischemic insult and parenchymal volume loss due to renal resection [4,19]. In surgeries other than nephrectomy, AKI is closely associated with the development of CKD and increased mortality [5,20,21].…”

Validation of new baseline renal function predictive model in robotic‐assisted partial nephrectomy cohort

“…created and validated an equation that utilizes preoperative eGFR, surgery type, age, preoperative imaging tumor size, and the presence/absence of diabetes to predict new baseline postoperative GFR values (NB‐GFR) following radical and partial nephrectomies. The equation was found to be >80% accurate for the developmental and validation cohorts in predicting new baseline renal function 3–12 months following surgery 1 . In the Palacios study, accuracy was defined as the percentage of predicted NB‐GFR that were within ±30% of the observed NB‐GFR.…”

“…The ability to predict renal function following renal surgery can aid urologists in deciding whether radical nephrectomy or partial nephrectomy would provide the best outcome 1,2 . Predicting postoperative estimated glomerular filtration rate (eGFR) following renal surgery has been previously attempted with various models: predicting percentage of preserved parenchymal mass, associating patient specific clinical factors with post‐operative renal function, and evaluating preoperative proteinuria 1–6 . Aguilar Palacios et al.…”