Stereotactic ablative radiotherapy for unresectable inferior vena cava tumor thrombus in a patient with renal cell carcinoma: a case report

Purpose Treatment options for renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVC-TT) are limited and carry substantial risks. Currently, there are no standard treatment options in the setting of recurrent or unresectable RCC with IVC-TT. Methods We report our experience of treating an IVC-TT RCC patient with stereotactic body radiation therapy (SBRT). Results This 62-year-old gentleman presented renal cell carcinoma with IVC-TT and liver metastases. Initial treatment consisted of radical nephrectomy and thrombectomy followed by continuous sunitinib. At 3 months, he developed an unresectable IVC-TT recurrence. A fiducial marker was implanted into the IVC-TT by catheterization. New biopsies were performed at the same time, demonstrating a recurrence of the RCC. SBRT consisted of 5 fractions of 7 Gy to the IVC-TT with excellent initial tolerance. He subsequently received anti-PD1 therapy (nivolumab). At 4 years follow-up, he is doing well with no IVC-TT recurrence and no late toxicity. Conclusion SBRT appears to be a feasible and safe treatment for IVC-TT secondary to RCC in patients who are not candidates for surgery.