Preoperative Nomograms for Predicting Renal Function at 1 Year After Partial Nephrectomy.

Area of Science:

• Nephrology
• Urology
• Oncology

Background:

• Partial nephrectomy (PN) is crucial for kidney cancer treatment, but can lead to chronic renal insufficiency (CRI).
• Predicting post-PN renal function is vital for patient counseling and managing expectations regarding potential dialysis.
• Current methods for predicting renal function post-PN are limited.

Purpose of the Study:

• To develop and validate nomograms predicting estimated glomerular filtration rates (eGFRs) one year after PN.
• To utilize only preoperative patient and tumor characteristics for prediction.
• To compare prediction accuracy using Modification of Diet in Renal Disease (MDRD) and CKD-EPI formulae.

Main Methods:

• Retrospective analysis of 461 patients undergoing PN between 2004 and 2016.
• Identification of preoperative covariates associated with 1-year post-PN eGFR using correlation and t-tests.
• Construction and internal validation of two multivariate linear regression nomograms (MDRD and CKD-EPI based).

Main Results:

• The incidence of eGFR below 60 mL/min/1.73 m² increased from 25% pre-PN to 35% at 1 year post-PN.
• Key predictors included age, race, BMI, pre-op creatinine, renal volume, solitary kidney status, tumor size, hypertension, diabetes, and cardiovascular history.
• Internal validation yielded good predictive performance with R-squared values of 0.61 (MDRD) and 0.70 (CKD-EPI).

Conclusions:

• Two validated nomograms accurately predict 1-year post-PN eGFR using preoperative data.
• These nomograms can aid clinicians in patient counseling and expectation management.
• The predictive models offer a valuable tool for personalized risk assessment in patients undergoing PN.