Drs. Goodnough and DiPersio should be commended for contributing such a well-written, well-referenced, objective, and authoritative review of issues in the management of cancer-related thrombocytopenia. Their article focuses primarily on platelet transfusion risks, rational transfusion thresholds, and potential novel pharmaceutical triumphs. The general lack of large-scale, definitive clinical trials in this field is appreciated and emphasized throughout. Much to my disappointment, the authors seem to have passed on the opportunity to provide the oncology community with any form of evidence-based (or evidence-lacking, as the case may be) and practical guideline for the treatment of thrombocytopenia.
The authors begin by cataloging recognized platelet transfusion-related complications. They do so in a manner not intended to criticize current platelet concentrate collection, storage, and infusion methods but rather to provide a perspective on the risks that must be considered and outweighed by anticipated benefits before platelet transfusion seems prudent. These principles are somewhat universal and should be routinely applied to all forms of blood product transfusion.
Leukoreduction is generally characterized as a methodology to modify platelet products in order to reduce risk without a clearly demonstrated impact on clinical outcomes. This comment is based on the fact that despite a statistically significant reduction in transfusion-related alloimmunization to platelets from 13% in leukemic patients receiving unprocessed platelets to from 3% to 5% in those receiving leukoreduced products, no difference in other meaningful outcomes was observed. The authors’ personal "position" on the use of leukoreduction technologies is unfortunately summed up by their reference to a more than 10-year-old set of published guidelines deemed to be still applicable. My guess is that the authors’ true feelings are reflected in what they actually do on a day-to-day basis. Such insight would have been welcome.
A great difference likely exists between published (recommended) safe platelet transfusion thresholds and clinically utilized and comfortable (standard of care) thresholds. Published thresholds often imply or require uniformity of thrombocytopenia etiology, patient concomitant illness, and underlying hemorrhagic risk. In the absence of a prudent set of recommendations and/or guidelines, practicing physicians will continue to transfuse in response to a higher platelet count threshold, with less regard for long-term complications and less attention to cost. To the practicing physician, the perceived needs of an individual patient at a particular moment in her/his care supersedes concerns about future complications and resource conservation. We can all agree that, ideally, the patient should be treated, not his/her platelet count.
Pharmacologic agents for the treatment of cancer-related thrombocytopenia hold some promise. It seems logical to establish clear thresholds for platelet transfusion before we can have a working understanding of what threshold to use for pharmacologic treatment.
I wonder how willing I would be (or any hematology/oncology colleague, transfusion medicine specialist, or the authors would be) to receive nonleukoreduced platelets only when the platelet count falls to 10,000/µL in the setting of leukemia or intensive cytoreductive therapy. I know I would be uncomfortable with this approach, regardless of the published data.