Epstein-Barr virus (EBV)-associated post-transplant
lymphoproliferative disorder (EBV-PTLD) is a complication of
hematopoietic stem cell transplantation (HSCT). Standard initial treatment of patients with EBV-PTLD includes administration of
rituximab or
dose reduction of a
calcineurin inhibitor. We report successful chemotherapeutic treatment of
rituximab-resistant EBV-PTLD after HSCT in a patient with severe
aplastic anemia (AA). A 38-year-old woman with
antithymocyte globulin (ATG)-resistant severe AA received
bone marrow transplantation from an unrelated donor (
human leukocyte antigen-DR single-locus mismatch). The conditioning regimen included
fludarabine,
cyclophosphamide, ATG, and total body irradiation, and prophylaxis for
graft-versus-host disease consisted of short
methotrexate and
tacrolimus. Neutrophil engraftment occurred on day 21. Left cervical lymph node swelling was observed after day 45, and analysis of a biopsy specimen revealed EBV-PTLD and a high blood EBV load (56,000 copies). The patient was treated with
rituximab 4 times per week, but the
lymphadenopathy continued and the blood EBV load increased to 96,000 copies. Half-dose treatment with
rituximab,
cyclophosphamide,
vincristine,
doxorubicin, and
prednisolone (R-CHOP) was initiated on day 71. After 32 days of treatment with R-CHOP, the patient's neutrophil level was restored to > 0.5 × 10(9)/L and both the
lymphadenopathy and the blood EBV load (< 100 copies) were rapidly reduced. Although
chemotherapy is not preferred soon after HSCT, it may be an effective strategy for treating patients with
rituximab-resistant EBV-PTLD.