Burkitt Lymphoma With Aberrant Expression of Cytoplasmic Terminal Deoxynucleotidyl Transferase: A Case Report

This study describes a rare case of Burkitt lymphoma with aberrant expression of cytoplasmic terminal deoxynucleotidyl transferase (TdT). Flow cytometry demonstrated a predominantly mature B cell immunophenotype as expected for Burkitt lymphoma, however, the immature marker TdT was also expressed. Immunohistochemistry showed that TdT was localized to the cytoplasm, with absent nuclear localization. The patient received standard intensive chemotherapy for Burkitt lymphoma and has remained in remission for nine years. Pathologists should be aware of this unusual phenomenon of aberrant cytoplasmic TdT expression to avoid confusing Burkitt lymphoma with B cell lymphoblastic leukemia/lymphoma.