Racial differences in mycosis fungoides: a retrospective study with a focus on eosinophilia.

Abstract

Mycosis fungoides (MF) is often associated with eosinophilia and portends a poorer prognosis. MF is more common in blacks and follows a more aggressive course compared with whites. We further elucidate racial differences between blacks and whites with MF, focusing on blood eosinophilia. The records of 345 patients with MF were reviewed for demographic, clinical, and pathologic data and evaluated by analysis of variance. The average age at diagnosis for blacks was 45 years and was 55 years for white patients (P < .001). In the cohorts of patients with and without blood eosinophilia, the average maximum blood eosinophil count had a greater range in blacks. Independent of race, blood eosinophilia was predictive of more advanced disease (P < .0001), increased number of treatment types (P < .002), and less responsiveness to treatment (P < .0006). This was a retrospective study at a single institution. These differences observed in eosinophil values may highlight disparities in MF diagnosis or a difference in pathophysiology between races.