Changes of plasma EBV DNA during treatment of EBV-positive lymphomas. (A) A case of diffuse large B-cell lymphoma. EBV DNAdropped to undetectable levels after initial chemotherapy, However, with relapses, EBV DNA rose again to significant levels. Successful treatment with salvage chemotherapy led to persistently undetectable levels of EBV. The patient had remained in continuous complete remission. (B) A case of angioimmunoblastic T-cell lymphoma. EBV dropped to undetectable levels after initial chemotherapy. On relapse, there was no response to chemotherapy and EBV DNA remained elevated until death. CEOP indicates cyclophosphamide, epirubicin, vincristine, prednisolone; DHAP, cisplatin, cytosine arabinoside, dexamethasone; IMVP16, ifosfamide, methotrexate, etoposide; anti-CD20, rituximab, ProMACE-CytaBOM: cyclophosphamide, adriamycin, etoposide, prednisolone, cytosine arabinoside, bleomycin, vincristine, methotrexate; and +, death.