Effect of renal embolization in patients with synchronous metastatic renal cell carcinoma: a retrospective comparison of cytoreductive nephrectomy and systemic medical therapy

OBJECTIVE: To compare survival outcomes for renal embolization (RE) to cytoreductive nephrectomy (CN) and no primary renal treatment (NT) among patients with synchronous metastatic renal cell carcinoma (mRCC) treated using either targeted therapy (TT) or immunotherapy (IT). RESULTS: The median follow-up duration was 81.3 months, with a duration of first-line treatment of 3.5 months. Among the 211 patients, the median PFS and OS were 4.4 and 10.6 months. Specifically for patients receiving TT (124 patients), the PFS and OS were 5.5 and 12.0 months. An intervention effect was identified only for OS, with a median OS of 20.1, 8.8 and 9.3 months for CN, RE and NT, respectively. After stratification by risk classification, CN provided a significant benefit on OS, compared to RE and NT, for patients with an intermediate risk (MSKCC). For those with a poor risk (Heng criteria), NT provided better survival than PFS (p=0.003), and a comparable survival to RE (p > 0.05). MATERIALS AND METHODS: Retrospective analysis of 211 patients, 87 treated with IT and 124 with TT, retrieved from our RCC database. Patients' risk factors for survival was evaluated using the Heng and MSKCC criteria, with only patients with an intermediate or poor survival risk included in the analysis. Between-group comparisons were evaluated with respect to progression-free survival (PFS) and overall survival (OS). CONCLUSIONS: The differential effect of CN and RE on OS appears to be modulated by risk classification. In patients with a poor risk, RE should be implemented after careful consideration of comorbidities and life expectancy.