A 61-year-old female was diagnosed with a lymphoid crisis of chronic myeloid leukemia (CML) in February 201X and started chemotherapy combined with dasatinib (DAS). After 1 month of initiating second consolidation therapy, the neutrophils decreased to 1%, bone marrow examination revealed large granular lymphocytes (LGL) at 13%, and complete cytogenetic remission was attained (CCyR). Suspecting DAS-induced agranulocytosis, DAS was discontinued. After 2 weeks, LGL disappeared and neutrophils recovered. In this case, CCyR was attained for the first time when LGL increased. We considered that the expansion of LGL correlated with the clinical efficacy, and agranulocytosis was an off-target effect of DAS.
Keywords: Agranulocytosis; Dasatinib; Large granular lymphocyte; Off-target effect.