Successful treatment of renal cell carcinoma with mediastinal lymph node metastasis by interleukin-2: a case report.

A 57-year-old woman presented to our hospital with macrohematuria. Renal cell carcinoma (RCC) of the left kidney with bilateral pulmonary and mediastinal lymph node metastases was diagnosed. Radical nephrectomy was performed. Pathological examination confirmed the diagnosis of RCC (pT2pN0M1), so immunotherapy was performed using interleukin-2 (IL-2). The mediastinal lymph node metastases disappeared completely after 5 months of immunotherapy. Investigation of immunological parameters showed an increase of CD8-positive T cells (CD8) and a decrease of CD14-positive cells (CD14), leading to a marked increase of the CD8/CD14 ratio. Although her pulmonary metastases are unchanged, the mediastinal metastases still show complete remission at 14 months postoperatively. The CD8/CD14 ratio may have potential as a new marker for monitoring the response of RCC to immunotherapy and selecting suitable patients for such therapy.