[Immunoblastic lymphoma after bone marrow graft. Apropos of a case treated by OKT3 monoclonal antibodies for an acute graft versus host reaction].
The incidence of malignant lymphoma after bone marrow transplant seems very low. A 31 years old patient was treated with allogeneic bone marrow transplantation for chronic myeloid leukemia; she develops 12 days after grafting a severe graft-versus-host disease (GVH) refractory to treatment with steroids and Cyclosporin A. The GVH was then treated with an anti-T lymphocyte monoclonal antibody (OKT3). The disease responded dramatically to this treatment but the GVH reappeared immediately at the end of OKT3 therapy and the patient died the 103th day after grafting. The autopsy revealed extensive lymphoid infiltrate by a monoclonal IgM K immunoblastic proliferation. After organ or bone marrow transplant, a wide spectrum of lymphoid lesions can be observed, ranging from follicular or diffuse polyclonal hyperplasia to monoclonal immunoblastic lymphoma. The criteria for monoclonality are discussed. Epstein-Barr Virus infection associated with immunosuppressive treatments play probably a major role in the occurrence of a malignant lymphoma.