Possible Association of CD3+CD4-CD8- Phenotype of T-Cell Lymphoma with Peripheral Blood Eosinophilia.

Introduction: Because the prognosis of patients with peripheral T-cell lymphoma is poor compared to that of patients with B-cell lymphoma, we want to avoid further organ damage by eosinophilia. Moreover, in patients with some types of lymphoma, blood eosinophilia is implicated in a worse prognosis. To study the risk factors of eosinophilia, the association between lymphoma type, immunophenotypic features, and peripheral blood eosinophil counts were examined in the patients with mature T-cell lymphoma.

Methods: We retrospectively examined 28 patients with mature T-cell lymphoma who were admitted to our hospital and whose immunophenotypic features were confirmed using flow cytometric, immunohistochemical analysis, or both between December 2012 and November 2023.

Results: We report a possible association between peripheral eosinophilia and peripheral T-cell lymphoma - not otherwise specified and CD3+CD4-D8- (double-negative) phenotypes. Mild eosinophilia was observed in various types, but moderate and severe eosinophilia were observed in patients with peripheral T-cell lymphoma - not otherwise specified. Double-negative phenotype was rarely observed; however, all patients with double-negative phenotype exhibited peripheral blood eosinophilia. In addition, four of the five cases of the double-negative type were peripheral T-cell lymphoma - not otherwise specified.

Conclusion: Here, we retrospectively examined patients with peripheral T-cell lymphoma whose immunophenotypic features were confirmed and report a possible association between peripheral eosinophilia and peripheral T-cell lymphoma - not otherwise specified and CD3+CD4-CD8- (double-negative) phenotypes. In addition, clinicians should be aware of the possible risk that patients with lymphocytic hypereosinophilic syndrome of the double-negative phenotype may develop peripheral T-cell lymphoma.