[Continuous subcutaneous injection therapy with interferon-alpha for renal cell carcinoma patients with bone metastasis].

Thirteen patients with renal cell carcinoma who had proven bony metastases were treated with multimodal treatment including surgery, radiotherapy and immunotherapy in the form of subcutaneous continuous injection of by natural type interferon-alpha (INF). The mode of administration of IFN was as follows: IFN, 2,5000 x 10(4) unit dissolved in 60 ml saline, was continuously injected (0.5 ml/hr) via a subcutaneous route as one course of the treatment and was given two courses in two weeks preoperatively. Postoperatively, IFN was given every week and the number of courses totally amounted to 15. In some cases IFN was given thereafter either every week or every other week. In four patients whose serum concentration of IFN was measured during and after administration of continuous IFN, the concentration of IFN rose after injection and showed 40.5 IU/ml in average 24 hours later. The concentration was kept measurable in six to eight days long and the maximum concentration was 167 IU/ml. In IFN-treated patients nine survived including two CRs, two NCs, five PDs and four deaths. The five year survival rate was 53%. Continuous subcutaneous injection of IFN in combination with surgery and/or radiotherapy is effective in the treatment of bony metastasis from renal cell carcinoma.