Impact of tumor dissecting technique on trifecta achievement in patients requiring extended warm ischemia during robot-assisted partial nephrectomy.

Purpose: To clarify specific factors associated with surgical outcomes in robot-assisted partial nephrectomy (RAPN) that require extended warm ischemia time (WIT), which may have a negative impact, but cannot always be avoided.

Methods: We included 1,182 patients who had RAPN performed between January 2016 and December 2022 from a prospectively generated multi-institutional RAPN database, divided into normal WIT (nWIT) (≤ 20 min; 843 patients) and extended WIT (eWIT) (> 20 min; 339 patients) groups. Primary outcome measures were WIT and the Surface-Intermediate-Base (SIB) margin score, which contribute to postoperative trifecta achievement. Results were compared between the two groups using logistic regression.

Results: Patients in the eWIT group had larger tumors, higher RENAL nephrometry scores, and lower SIB scores than those of the nWIT group. The trifecta achievement rate was significantly different between the two groups (nWIT: 70.1 vs. 49.0%, p < 0.001). In the nWIT group, WIT (coefficient: -0.105 [standard error 0.020], p < 0.001) and SIB score (coefficient: -0.107 [0.053], p = 0.045) were significant predictors of trifecta achievement. In the eWIT group, the SIB score (coefficient - 0.216 [0.082], p = 0.008) was significantly associated with trifecta attainment, whereas WIT only showed a trend toward significance. Limitations included a lack of long-term survival, renal function, and chronic complications data.

Conclusions: For patients with eWIT during RAPN, the tumor dissection technique may be more important than WIT in predicting postoperative outcomes. Further prospective studies are required to confirm our results.