A case of renal cell carcinoma with multiple lung metastases refractory to interferon-α showing complete remission by interleukin-2 monotherapy

We report a case in which a regimen of interleukin-2 (IL-2) achieved pathologically complete remission against renal cell carcinoma with multiple lung metastases. A 63-year-old man was admitted to the Osaka University Hospital with a right renal tumor and multiple lung metastases. Right radical nephrectomy was performed and the histological diagnosis was clear cell carcinoma, G3 > G2, INFbeta, pT3a, pN0. Postoperatively, despite treatment with interferon-alpha, the lung metastases progressed. Consequently, intravenous administration of IL-2 was started at a dose of 70 x 10(4) JRU/day five times per week. After 16 weeks of IL-2 therapy, most of the multiple lung metastases completely vanished and the largest metastatic lung mass was reduced in size. Resection of this residual lung mass was performed and pathological examination revealed no viable cancer cells.