Abstract
OBJECTIVE: Renal cell carcinoma (RCC) has a unique feature in which tumor thrombus extends through the vein into the inferior vena cava. RCC with venous tumor thrombus is classified based on the level of thrombus. Standard treatment involves a combination of radical nephrectomy and tumor thrombectomy, despite the technical challenges associated with this approach. We aimed to evaluate the clinical outcomes based on the tumor thrombus level. METHODS: We conducted a retrospective analysis of patients who underwent tumor resection and thrombectomy for RCC with venous tumor thrombus at a single center between January 2001 and December 2022. Tumor thrombus levels were classified into four levels (I-IV) according to the Mayo Clinic grading system, and patients were grouped based on the hepatic vein level: levels 0, I, and II were categorized as group 1, while levels III and IV were categorized as group 2. Survival outcomes were compared between the two groups using Kaplan-Meier survival analysis. RESULTS: A total of 287 patients with RCC with venous tumor thrombus who underwent tumor resection and thrombectomy were identified. The distribution of patients according to the tumor thrombus level was as follows: 84 patients had level 0 thrombus, 71 had level I, 85 had level II, 19 had level III, and 28 had level IV. This results in 240 patients in group 1 (levels 0, I, and II) and 47 patients in group 2 (levels III and IV). The 5-year survival rates were 46.7% for group 1 and 53.2% for group 2. Kaplan-Meier survival analysis showed no significant difference in 5-year overall survival between the two groups (P = .75). However, patients in group 2 had a significantly longer postoperative hospital stay (21.43 ± 23.09 days) compared with those in group 1 (10.63 ± 6.31 days; P = .004). CONCLUSIONS: Tumor thrombus level is not a significant prognostic factor in RCC. Aggressive surgical removal should be considered, even for thrombus extending beyond the hepatic vein, given the acceptable prognosis.