Partial Nephrectomy vs Thermal Ablation for Non-Clear Cell RCC: The UNCLEAR Study (UroCCR 172)

Purpose To compare disease-free survival (DFS) between partial nephrectomy (PN) and percutaneous ablation (PCA) in patients with non-clear cell renal cell carcinoma (nccRCC), and to identify independent predictors of disease recurrence. Methods We performed a retrospective, propensity score-matched analysis of prospectively collected data from the UroCCR registry, including 31 centers (2009–2023). Patients with histologically confirmed cT1a nccRCC treated by PN or PCA were included. Propensity matching (2:1) was based on previous RCC history, tumor size, and histological subtype. DFS was defined as time to first recurrence documented on computed tomography. Results After propensity matching, 174 patients were included (PN n = 116; PCA n = 58). Median follow-up was 3.2 years, with 18 recurrences. Five-year DFS was significantly higher after PN than PCA (88.7% vs. 76.8%; HR = 3.11, 95%CI 1.21–8.01; p = 0.018). Previous RCC was the strongest independent predictor of worse DFS in multivariate analysis (HR = 6.23, 95%CI 2.49–15.58; p < 0.01). In univariate exploratory subgroup analyses, the DFS advantage of PN was most pronounced in pRCC (HR = 3.44, 95%CI 1.03–11.46; p = 0.044) and in patients without prior renal malignancy (HR = 6.49; p = 0.005), whereas no statistically significant difference was observed in chRCC. The difference was no longer significant in a post hoc sensitivity analysis restricted to R0 PN and excluding early local recurrences after PCA (HR = 1.85, 95%CI 0.55–6.23; p = 0.32). Conclusion In cT1a nccRCC, PN was associated with longer DFS than PCA after propensity matching, particularly in pRCC. Overall survival impact needs prospective evaluation.