Epstein-Barr virus-associated lymphoproliferative disease during remission after induction therapy with dasatinib in Philadelphia chromosome-positive acute lymphoblastic leukemia: a case report.

Dasatinib, a second-generation tyrosine kinase inhibitor, has been reported to have immunomodulatory effects. Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (EBV-LPD) occur in immunocompromised patients, such as those receiving methotrexate or other immunosuppressive drugs or after allogenic transplantation. EBV-LPD is also reported to be a rare side effect in patients receiving long-term dasatinib or imatinib. The present report describes a 60-year-old woman with Philadelphia chromosome-positive acute lymphoblastic leukemia who was treated with dasatinib and prednisolone for induction of remission. Fever, enlargement of the tonsils, multiple cervical lymphadenopathies and a splenic mass emerged after 1 month of treatment. Histopathological analysis of tonsil biopsy specimens showed diffuse proliferation of CD20-positive atypical cells with large, irregular nuclei. Some of these cells were positive for EBV-encoded small RNA, and her peripheral blood was positive for EBV-DNA (4.9 Log IU/mL), leading to a diagnosis of EBV-LPD. After discontinuation of dasatinib, her high fever and cervical lymphadenopathies disappeared without recurrence. The subsequently removed splenic mass was largely composed of non-neoplastic cytotoxic T cells resulting from a reaction to EBV-infected B cells. EBV-LPD should be included in the differential diagnosis of patients who develop lymphadenopathy during dasatinib treatment, regardless of its duration.