Impact of neoadjuvant therapy on prognosis in renal cell carcinoma with inferior vena cava thrombus.

Background: The standard treatment for non-metastatic renal cell carcinoma (RCC) with inferior vena cava (IVC) thrombus is complete surgical resection; however, this procedure is complex and carries high complication rates and perioperative mortality. Previous studies have explored preoperative multimodal therapy to reduce surgical difficulty, but limited evidence prevents guideline recommendations. This study aimed to investigate the impact of neoadjuvant therapy on the prognosis of patients with RCC and IVC thrombus without distant metastasis.

Methods: Data from 2006 to 2024 on RCC patients with IVC thrombus undergoing radical nephrectomy plus IVC thrombus resection were collected. Patients received neoadjuvant therapy, including tyrosine kinase inhibitors or immune checkpoint inhibitors, followed by surgery. Tumor size and thrombus height were assessed by computed tomography. Disease-free survival (DFS) and overall survival (OS) were calculated using Kaplan-Meier curves. Multivariate analysis was used to identify factors predicting DFS.

Results: Thirty-one patients who did not receive neoadjuvant chemotherapy therapy (NAC-Naive group) and 19 patients who received neoadjuvant chemotherapy therapy (NAC group) were analyzed. The NAC group showed significant reductions in primary renal tumor size and neutrophil-to-lymphocyte ratio compared to the NAC-Naive group just before nephrectomy. The NAC group had significantly improved DFS and OS. Median DFS and OS were not reached in the NAC group compared to 26.3 months and 73.5 months, respectively, in the NAC-Naive group. The NAC group had a 2-year recurrence-free survival rate of 70.9% compared to 50.6% in the NAC-Naive group. Multivariate analysis identified a preoperative tumor size of 10 cm or larger and lack of neoadjuvant therapy as poor prognostic factors for DFS.

Conclusion: Neoadjuvant therapy significantly improves the prognosis of RCC patients with IVC thrombus. This therapy reduces surgical invasiveness and has a mid- to long-term preventive effect on recurrence. These findings support the potential benefit of neoadjuvant systemic therapy in improving outcomes for this patient population.