Ethnic neutropenia among women of European, African, and Caribbean backgrounds

Abstract

6587 Background: Black women are less likely than white women to receive complete chemotherapy for cancer. One reason for interruption of chemotherapy may be a patient's low white blood count (WBC) or absolute neutrophil count (ANC). In studies of white blood cell count (WBC) and race, white individuals’ WBC has been considered the standard, and 25–40% of non-Hispanic black individuals have been described as having “benign ethnic neutropenia.”. We therefore studied the prevalence and severity of ethnic neutropenia among women in six ethnic groups and of the association between neutropenia and serum cytokine and C-reactive protein (CRP) levels and neutrophil elastase (ELA2) polymorphisms. Methods: Following IRB approval, each participant provided a blood sample that was tested for WBC with differentials, cytokines and CRP levels, and ELA2 polymorphisms. We compared median WBC and ANC using Kruskal-Wallis tests. We used Fisher's exact tests to analyze association of severe neutropenia with ethnicity, cytokine and CRP levels, and ELA2 polymorphisms. Results: We enrolled 263 women 20–70 years old who had no cancer diagnosis.. As the table shows, median WBC and ANC differed by group; Dominicans had significantly higher median WBCs and ANCs than all other groups. Of 12 women with severe neutropenia (ANC = 1,500), none was Dominican or European-American. Subjects with a common upregulating ELA2 promoter polymorphism (C-199A) had lower ANC counts than other subjects. No associations were found between ANC counts and either cytokines or CRP levels. Conclusions: Median WBC and ANC and severe neutropenia were associated with ethnicity. Mild neutropenia is considered clinically benign, but because severe neutropenia may result in decreased doses or delays in chemotherapeutic treatment for malignancies, ethnic neutropenia and its role in treatment decisions requires further investigation. No significant financial relationships to disclose. [Table: see text]