Cancer-related thrombocytopenia is a clinical problem. Unfortunately, the qualitative nature and quantitative extent of the problem has been poorly defined to date. Without knowing these two parameters, the risk/benefit ratio of any management option for cancer-related thrombocytopenia is impossible to calculate accurately. Drs. Goodnough and DiPersio have done an excellent job of delineating many of the potential risks of managing the problems associated with platelet transfusions.
Although transfusion-related viral infections are high on the list of potential toxicities, data suggest that, with the exception of cytomegalovirus (CMV), these occur infrequently. Transfusion-related bacterial infections are not often considered to be a serious clinical problem. However, if one considers that the risk of sepsis with apheresis platelets is 1 in 12,000 and the mortality rate associated with this sepsis is 26% (as the authors suggest), then patients receiving 10 platelet transfusions over the course of their cancer therapy have a 1 in 4,800 risk of death from transfusion. That is not a negligible risk, especially in light of the number of patients who undergo myelosuppressive treatments for cancer.
Platelet Refractoriness and Other Limitations
Refractoriness to platelet transfusion due to alloimmunization is listed as a potential problem with the use of transfusion therapy, but its clinical significance may be overestimated given the lack of clinical improvement seen in patients in whom alloimmunization was prevented with the use of leukoreduced platelets.
The financial expense of platelet transfusion therapy was briefly mentioned, but deserves more detailed consideration. In calculating its expense, the cost of all factors associated with the collection of platelets for transfusion (including, for example, time off from work for the platelet donors) should be included. These factors are often not accounted for in such analyses.
Another potential downside to platelet transfusions that is not often mentioned in this type of review is their potential contribution to the complications that occur after administration of chemotherapy. In blood and marrow transplant patients, increased use of prophylactic platelet transfusion is associated with subsequent development of hepatic veno-occlusive disease, pulmonary dysfunction, and central nervous system (CNS) dysfunction. Although this association does not confirm a causative role for platelet transfusions in the generation of CNS, pulmonary, or hepatic complications, data from animal models and other clinical disorders suggest this possibility.[3-5]
Level of Supportive Evidence