DDD Score Outperforms RENAL and PADUA in Predicting Ischemia Time and Trifecta Outcomes in Laparoscopic Partial Nephrectomy

Abstract

Objectives:

Renal cell carcinoma (RCC) is commonly treated with partial nephrectomy (PN) for localized disease. Nephrometry scores like RENAL and PADUA assist in assessing tumor complexity and guiding surgical planning. The DDD (Diameter, Depth, Distance) score has recently emerged as a simplified alternative, though comparative data remain limited.

Methods:

This retrospective study analyzed 144 RCC patients who underwent PN between 2018 and 2024. Tumor complexity was assessed using DDD, RENAL, and PADUA scores. Perioperative outcomes, including ischemia time, operative time, hospital stay, complications, and trifecta achievement, were evaluated. Predictive performance of these three system was compared using receiver operating characteristic curves and area under the curve (AUC) analysis.

Results:

The DDD score showed significant correlations with key perioperative metrics. Ischemia time increased with DDD complexity categories (low: 10.50 ± 9.82 minutes; moderate: 15.33 ± 11.23 minutes; high: 17.92 ± 9.77 minutes; P = .006). Similarly, operative time (low: 2.11 ± 0.48 hours; moderate: 2.95 ± 1.13 hours; high: 2.84 ± 0.90 hours; P = .001) and length of hospital stay (low: 3.79 ± 1.29 days; moderate: 4.33 ± 1.57 days; high: 5.59 ± 2.93 days; P = .001) demonstrated significant differences across DDD categories. The DDD score outperformed RENAL and PADUA scores in predicting ischemia time >25 minutes (AUC: 0.64) and trifecta outcomes, with significant predictive value (P = .038).

Conclusion:

The DDD score is a simple and effective tool for assessing surgical complexity in RCC. It demonstrates superior predictive utility for ischemia and operative time compared with traditional nephrometry systems and may aid in perioperative planning. However, further prospective validation is warranted.