The Impact of Renal Tumor Surgery on Kidney Function

New baseline estimated glomerular filtration rate (GFR) after renal tumor surgery can be a strong predictor of survival and stability of renal function, particularly in patients with reduced preoperative renal function. Surgery can independently lead to the development or progression of chronic kidney disease (CKD). In appropriately selected patients, partial nephrectomy (PN) offers the advantage of better functional preservation than radical nephrectomy (RN), along with comparable oncological efficacy. As such, PN has been adopted as standard of care for small renal masses even in patients with a normal contralateral kidney. Larger renal masses have increased oncologic potential and RN should be considered, particularly if there is high tumor complexity, no preexisting CKD or proteinuria, and a normal contralateral kidney. Recent data suggest that patients with CKD primarily due to surgical removal of nephrons have survival similar to those with no CKD even after surgery, particularly if new baseline eGFR is >45 ml/min/1.73 m2. In contrast, patients with preexisting CKD typically have unstable renal function and substantially worse survival and PN should be prioritized in this cohort whenever feasible. In this setting, efforts to optimize functional outcomes with PN are particularly important. Quality and quantity of vascularized parenchymal mass are the primary determinants of functional recovery after PN, while ischemia characteristics play a secondary role. Quantity of vascularized parenchyma preserved can be optimized by limiting the amount of parenchyma excised along with the tumor and reducing devascularization that can occur during the reconstructive phase of the procedure.