Current status of leukocyte and platelet administration in cancer therapy.

Leukapheresis and plateletpheresis are rather commonly performed in order to obtain single donor concentrates of granulocytes and platelets. These procedures, although relatively safe, present occasional risks to donors and recipients. Some of the occasional adverse problems experienced by donors include citrate toxicity or acute hypocalcemia, hypotension, hypervolemia, venospasm or vein occlusion, chills, anaphylactoid reactions, hemorrhage, abdominal pain or complications related to equipment failure and related technical problems. Potential risks to donors include those related to the receiving of six percent hydroxyethyl starch (HES), dextrans, or corticosteroids, lymphocyte depletion or immunosuppression, and effects on the complement system. Prophylactic granulocyte transfusions to prevent the occurrence of infections and associated complications in neutropenic patients have not proven to be efficacious; therapeutic granulocyte transfusions appear to be more effective. Indications for therapeutic granulocyte transfusions include those patients with known infections unresponsive to appropriately aggressive antibiotic chemotherapy over a two or three day period combined with findings of a peripheral granulocyte count less than 500 mm3 and especially those with counts below 100 mm3 and/or prolonged fever greater then 38 degrees C (100.4 degrees F) for 24 to 48 hours. In addition, the patient should have a reasonable chance for bone marrow recovery. Hazards or complications associated with granulocyte transfusions include: (a) immediate transfusion reactions, (b) hypersensitivity reactions, (c) pulmonary infiltrates, (d) alloimmunization, (e) transmission of infections, and (f) the possibility of Graft vs. Host (GVH) disease. The current best use of apheresis platelets is to provide therapeutic doses of single donor matched platelets for patients refractory to pooled random donor platelets. Alloimmunization represents the major complication of therapeutic platelet transfusion and is characterized clinically by the failure to achieve expected platelet count increments after transfusion. Future developments which might greatly improve the effectiveness of therapeutic and possibly prophylactic leukapheresis and plateletpheresis include the development of effective sedimenting agents with shorter biological half-lives, more efficient and less expensive methods of procurement of granulocytes and platelets, improved methods of cryopreservation of granulocytes and platelets, better methods for detecting and quantitating antigranulocyte and/or antiplatelet antibodies, and more efficient evaluation of possible synergism of granulocyte transfusions with antibiotic therapy and residual host defense. These improvements may be of great value in the effective utilization of granulocyte and platelet products and in determining which patients are most likely to receive the maximum benefit from granulocyte and platelet support.