Neutrophil Count in African Americans: Lowering the Target Cutoff to Initiate or Resume Chemotherapy?

Abstract

Inclusion and exclusion criteria for participation in clinical trials are meant to select patients who are appropriate for the disease under study and to protect clinical research subjectparticipants from undue risk related to the research. The selection criteria should not arbitrarily exclude subjects. In 1994, the National Institutes of Health (NIH) published guidelines on the inclusion of women and minorities in clinical trials. The guidelines were intended to ensure that women and members of minorities are included in all human subject research and specified that concerns for cost could not be viewed as an acceptable reason for excluding these groups. It is thus incumbent on researchers to ensure that undue barriers are not placed on groups of individuals that would cause their underrepresentation in publicly funded clinical research. Toward meeting these goals, the guidelines called for the initiation of programs and support for outreach efforts to recruit underrepresented groups into clinical studies. Although these efforts have led to the increased participation in some instances of previously excluded groups onto clinical trials, there may be circumstances where eligibility criteria can exclude participation of certain groups disproportionately. 1-4 Rigid requirement for minimal WBC numbers may be one such criterion deserving of further consideration in this regard. Benign ethnic neutropenia (BEN) is a condition used to describe individuals ofAfricandescentwithneutrophilcountslessthan1.510 9 cells/Lin theabsenceofothercauses 5 andconstitutesonesuchgroupforwhom minimalWBCnumbersmayarbitrarilyexcludefromparticipationin clinical trials. The risk of febrile neutropenia is determined by the durationanddepthofneutropenia,withtheriskgreatestwhenthe neutrophils are below 0.5 10 9 cells/L. 6-8 There are currently insufficientdatatoindicatethatindividualswithBENwouldfacea higher risk of febrile neutropenia greater than those without BEN. Therefore, BEN may unduly exclude clinical trials participation in a greater proportion of individuals from certain ethnic groups compared with others. It follows that exclusion of individuals with BENmaybeatoddswithNIHguidelinesaimedtowardenhancing