Sézary Syndrome Coexisting with B-Cell Chronic Lymphocytic Leukemia: Case Report and Review of the Literature

Introduction: The simultaneous presentation of chronic B-cell lymphocytic leukemia (B-CLL) and cutaneous T-cell lymphoma (CTCL) is extremely rare. Case Report: We describe a patient with B-CLL and Sézary syndrome (SS), an erythrodermic and leukemic variant of CTCL. Despite treatment, the SS progressed to involve internal organs and eventual death of the patient from sepsis. This is the first reported case of SS coexisting with chronic lymphocytic leukemia in which an anti-Vβ13.6 antibody was used to serially track changes in circulating neoplastic T cells vis-à-vis neoplastic B cells and to detect neoplastic T cells in ascitic fluid near the end of the patient’s life. Discussion: We speculate that the coexistence of B-CLL and CTCL is the result of an initiating genetic or epigenetic defect at the level of the common lymphoid stem cell that predisposes both B-cell and T-cell lineages to additional oncogenic changes at a more advanced stage of differentiation.