Chemoimmunotherapy in Advanced Renal Cell Carcinoma: A Case Report of a Long-Term Survivor Adjunctly Treated with Viscum album Extracts

Introduction: Metastatic renal cell carcinoma has a poor prognosis. Treatment approaches with immunotherapy show promising results in subpopulations. Viscum album extracts – used as an adjunct to cancer treatment – have cytotoxic, apoptogenic, and immune-stimulating properties and show synergistic effects with chemotherapy agents. Case Report: A 51-year-old man was diagnosed with metastatic renal cell carcinoma of clear cell histology which was classified as pT3a, N1, M1, G3. Nephrectomy was performed, and the patient received chemoimmunotherapy (interferon-α2a, interleukin-2, fluorouracil, isotretinoin). Additionally, he received V. album extracts as intravenous infusions and subcutaneous injections. One year after surgery, the patient was in complete remission, which is ongoing 18 years after the initial diagnosis. Discussion: This case shows an extraordinarily long survival of a metastasized renal cell carcinoma patient under chemoimmunotherapy and fever-inducing V. album extracts. This combined treatment might have synergistically contributed to tumor remission and control. With regard to clinical relevance, further investigations are needed.