Extracorporeal interferon therapy in malignant melanoma. Significant economies of interferon in an extracorporeal chamber.

A new method is described for interferon therapy. The procedure involves immobilization of interferon with maintained activity to the surfaces of an extracorporeal perfusion chamber made from polymethylmethacrylate, having a surface area of 0.5 m2 and housing 150 ml blood. The interferon activity remains for at least 3 weeks in a chamber used in patients. Three cases of malignant melanoma, stage II, were treated for 35 to 50 h. The treatment induced increased natural killer activity against melanoma target cells (cytotoxicity index +45--65%) which lasted even after cessation of therapy. the drastic reduction in costs for this type of interferon therapy is underlined.