Objective: To determine the most effective, evi- dence-based approach to the use of platelet transfu- sions in patients with cancer. Outcomes: Outcomes of interest included prevention of morbidity and mortality from hemorrhage, effects on survival, quality of life, toxicity reduction, and cost-effectiveness. Evidence: A complete MedLine search was per- formed of the past 20 years of the medical literature. Keywords included platelet transfusion, alloimmuniza- tion, hemorrhage, threshold and thrombocytopenia. The search was broadened by articles from the bibliog- raphies of selected articles. Values: Levels of evidence and guideline grades were rated by a standard process. More weight was given to studies that tested a hypothesis directly related to one of the primary outcomes in a randomized design. Benefits/Harms/Cost: The possible consequences of different approaches to the use of platelet transfusion were considered in evaluating a preference for one or another technique producing similar outcomes. Cost alone was not a determining factor. Recommendations: Appendix A summarizes the rec- ommendations concerning the choice of particular platelet preparations, the use of prophylactic platelet transfusions, indications for transfusion in selected clin- ical situations, and the diagnosis, prevention, and man- agement of refractoriness to platelet transfusion. Validation: Five outside reviewers, the ASCO Health Services Research Committee, and the ASCO Board re- viewed this document. Sponsor: American Society of Clinical Oncology J Clin Oncol 19:1519-1538. © 2001 by American Society of Clinical Oncology. INTENSIVE THERAPIES producing severe and sus- tained thrombocytopenia are used routinely in patients with hematologic malignancies and are being applied to many patients with solid tumors as well. Advances in platelet collection, storage, and transfusion have decreased the morbidity of such therapies, and death from hemorrhage is now an unusual occurrence, despite the larger number of patients being treated aggressively. Platelet transfusions are expensive, however, and are associated with a number of side effects including febrile or allergic transfusion reac- tions, transmission of bacterial and viral infections, circu- latory congestion, transfusion-related acute lung injury and alloimmunization. The ASCO Health Services Research Committee elected to convene an Expert Panel to design guidelines for platelet transfusion because of perceived wide variation in platelet transfusion practices. This paper will first describe the types of platelet products available for transfusion and then provide evidence-based guidelines for use in different clinical situations.

Platelet Transfusion for Patients With Cancer: Clinical Practice Guidelines of the American Society of Clinical Oncology*

Biologic effects of leukocytes present in transfused cellular blood products

Transfusion-associated graft-versus-host disease.

The platelet, a fascinating anucleate cell, is critically important for haemostasis. Platelet transfusions have greatly reduced the incidence of major haemorrhagic complications associated with the management of haematological and oncological disorders. However, some patients fail to receive the full benefit of platelet transfusions because they do not achieve the appropriate platelet count increment following transfusion. This review will discuss the aetiology, diagnosis, and management of refractoriness to platelet transfusion, a complicated problem for both the treating physicians and the transfusion services supporting these patients. Although advances have been made in the diagnosis and treatment of immune-mediated platelet refractoriness, which is usually caused by anti-human leucocyte antigen antibodies, non-immune causes, such as sepsis, remain problematic.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2141.2008.07189.x

Platelet transfusion refractoriness.

Survival of donor leukocyte subpopulations in immunocompetent transfusion recipients : Frequent long-term microchimerism in severe trauma patients

Recent studies have shown that the incidence of alloimmunization due to repeated platelet transfusions from random donors may be reduced by the use of leucocyte-poor blood components. These results were confirmed by this study, where 16% of patients with acute leukaemia undergoing initial chemotherapy and receiving leucocyte-poor blood components developed lymphocytotoxic antibodies, compared with 48% of patients in a control group receiving standard (non-leucocyte-depleted) blood components. In a third group, who received leucocyte-poor blood components and HLA-matched platelets, none of the patients developed lymphocytotoxic antibodies. There was a low incidence of platelet-specific antibodies (8%) but no difference between the three groups. Improved methods of removing leucocytes from blood components appear to offer the best approach for minimizing HLA alloimmunization, as the provision of HLA-matched platelet donors for prophylactic platelet support of all patients is not feasible.

H. Thomas

Papers

Use of leucocyte‐poor blood components and HLA‐matched‐platelet donors to prevent HLA alloimmunization