Tumor Thrombus of Renal Cell Carcinoma Extending Into the Inferior Vena Cava, Ovarian Vein, and Ureter Treated With Neoadjuvant Axitinib.

Ureter tumor thrombus (TT) of renal cell carcinoma (RCC) is quite rare, although RCC-TT in the inferior vena cava (IVC) is not uncommon. We report the first case of RCC-TT extending into the IVC and ovarian vein as well as the ureter. Neoadjuvant axitinib shrank both the primary tumor and TT, making radical nephrectomy less invasive, particularly by downleveling the IVC-TT. Pathological examination of the primary tumor, IVC-TT, and ureter TT showed clear cell carcinoma with extensive necrosis. Although the role of neoadjuvant axitinib in RCC remains unclear, the present case suggests that neoadjuvant axitinib is clinically beneficial for RCC-TT.