Resistance of tumour cells to chemotherapy: importance of host defence factors.

ABSTRACT

The arguments favouring the hypothesis that chemotherapeutic agents might act in cooperation with host defence mechanisms are reviewed briefly. In patients with far advanced solid tumours plasma factors blocking in vitro immune reactions have been identified and successfully removed by immune adsorption or plasma exchange. By plasmapheresis performed in patients with metastatic malignancies resistant to chemotherapy it was possible to induce tumour regressions. In 25/28 patients responding to the combined plasmapheresis/chemotherapy procedure a positive correlation was found to clinical results and patterns of plasma-blocking factor activities.