Efficacy of vertebral cryoablation and immunotherapy in a patient with metastatic renal cell carcinoma: a case report

BACKGROUND: In metastatic renal cell carcinoma, immunotherapy is the only treatment modality associated with a complete and durable response, but severe toxicity limits its usefulness. If toxicity could be eliminated, immunotherapy might be an effective treatment for metastatic renal cell carcinoma. We present a case of a patient with spinal metastatic renal cell carcinoma treated with total en bloc spondylectomy and reconstruction using a cryo-treated tumor-bearing bone graft; the patient demonstrated an antitumor cryoimmunological response. CASE PRESENTATION: A 51-year-old Japanese man presented with back pain 4 years after undergoing a left-sided total nephrectomy for renal cell carcinoma. He was diagnosed with metastases in the T1–T3 vertebrae, right adrenal gland, sternum, left clavicle, and sacrum. Total en bloc spondylectomy and reconstruction using a cryo-treated tumor-bearing bone graft was performed to treat the vertebral metastases. Sunitinib and then everolimus were also administered. Serum interferon-γ and interleukin 12 levels were measured before surgery and at 1, 3, 6, and 12 months after surgery. Serum interferon-γ and interleukin 12 levels increased 3 months after surgery; this increase was sustained for 6 months. No local recurrence or other distant metastases occurred. The bone metastases remained stable, and the adrenal metastasis progressed slowly. The duration of progression-free survival during sunitinib and everolimus treatment was 24 and 40 months, respectively, and overall survival is currently 5.5 years. CONCLUSIONS: This report demonstrates that using cryo-treated tumor-bearing tissue in a patient with metastatic renal cell carcinoma stimulated an antitumor cryoimmunological response.