External validation of yonsei nomogram predicting chronic kidney disease development after partial nephrectomy: An...

Area of Science:

• Nephrology
• Urology
• Oncology

Background:

• Partial nephrectomy (PN) is standard for cT1 renal masses.
• Predicting chronic kidney disease (CKD) post-PN is crucial for long-term outcomes.
• Existing nomograms require external validation for broader applicability.

Purpose of the Study:

• To externally validate the predictive accuracy of the Yonsei nomogram for new-onset CKD stage ≥III after on-clamp PN.
• To assess the calibration and discrimination of the Yonsei nomogram in a large, multi-center cohort.
• To evaluate the nomogram's utility in estimating CKD-free progression probabilities.

Main Methods:

• Retrospective analysis of 3526 patients undergoing on-clamp PN for cT1 renal masses across 23 centers (2000-2018).
• Inclusion criteria: two kidneys, preoperative eGFR ≥60 mL/min/1.73 m², and ≥12 months follow-up.
• External validation using calibration and discrimination analyses to assess the Yonsei nomogram's performance.

Main Results:

• 19.4% of patients developed new-onset CKD stage ≥III.
• The 5-year CKD-free progression rate was 77.9%.
• Yonsei nomogram showed good discrimination (AUCs ranging from 0.69 to 0.78) and calibration (slope values 0.75-0.83) for predicting CKD stage ≥III at various time points.

Conclusions:

• The Yonsei nomogram demonstrated good calibration properties in this large external validation cohort.
• The nomogram provides an accurate estimation of individual CKD-free progression risk.
• This tool can aid clinicians in managing patients undergoing partial nephrectomy for renal masses.