Repeated regression of pulmonary metastases from renal cell carcinoma after treatment using different interferon-alpha preparations.

A 49-year-old man with pulmonary metastasis from renal cell carcinoma (RCC) was treated with recombinant IFN-alpha2b (Intron A). A complete response was achieved within 4 months and thereafter persisted for 5 years until he developed another lung lesion. Interleukin-2 (Imunace) was administered without any response. Finally, he was treated by natural IFN-alpha (OIF). The pulmonary lesion achieved a partial response after 11 months of treatment. Because IFN-alpha preparations include different subtypes, changing the use of IFN-alpha preparations may thus be a potentially useful option for the successful immunotherapy of RCC.