Selective Use of Neoadjuvant Targeted Therapy Is Associated with Greater Achievement of Partial Nephrectomy for High-complexity Renal Masses in a Solitary Kidney

Background: Partial nephrectomy (PN) is preferred for a renal mass in a solitary kidney (RMSK), although tumors with high complexity can be challenging. Objective: To evaluate the evolution of RMSK management with a focus on achievement of PN. Design, setting, and participants: Patients with nonmetastatic RMSK (n = 499) were retrospectively reviewed; 133 had high tumor complexity, including 80 in the pre-tyrosine kinase inhibitor (TKI) era (1999–2008) and 53 in the TKI era (2009–2022). After 2009, 23/53 patients received neoadjuvant TKI and 30/53 had immediate-surgery. Outcome measurements and statistical analysis: Functional outcomes, adverse events and complications, dialysis-free survival, and recurrence-free survival (RFS) were the measures evaluated. Mann-Whitney and χ2 tests were used to compare cohorts, and the log-rank test was applied for survival analyses. Results and limitations: Overall, the median RENAL score was 10 and the median tumor diameter was 5.2 cm. Demographic characteristics, tumor diameter, and RENAL scores were similar between the pre-TKI-era and TKI-era groups. In the TKI era, 23/53 patients (43%) with clear-cell histology were selected for neoadjuvant TKI. These 23 patients had a greater median tumor diameter (7.1 vs 4.4 cm; p = 0.02) and RENAL score (11 vs 10; p = 0.07). After TKI treatment, the median tumor diameter decreased to 5.6 cm and the RENAL score to 9, and tumor volume was reduced by 59% (all p