Feasibility of extracorporeal on-line large-scale plasma adsorptions on protein A-sepharose columns in cancer patients.

: The feasibility of extracorporeal adsorption of 1.5-3 L plasma on protein A-Sepharose was investigated in six patients with advanced cancer. Anticoagulation with heparin was associated with respiratory distress syndrome in two patients, most likely caused by complement activation as indicated by a transient leukopenia during plasma reinfusion and appearance of C3 degradation products in the extracorporeal circulation. Addition of citrate abolished the respiratory symptoms, C3 degradation, and leukopenia, and no adverse reactions were observed. No objective tumor regression was observed in any of the patients. Three patients progressed during therapy. In one of these, multifocal central tumor necrosis was observed as a possible, although unproven, therapeutic effect. Increased natural killer and/or killer cell activities were recorded in three patients and increased complement-dependent serum cytotoxicity in one patient. The level of circulating immune complexes decreased significantly (18–28%) in three patients studied. It is concluded that extracorporeal plasma adsorption on protein A-Sepharose is feasible when citrate is added to the extracorporeal system, but its therapeutic efficacy is uncertain.