RESUMEN
In a patient with recently diagnosed chronic myelomonocytic leukemia features, the biopsy of a peripheral lymphadenopathy seven months later revealed disorganised lymphoid tissue with a few large EBER (+) LMP1 (+) B-lymphocytes before any treatment was given. At this time, a clonal TCR gamma rearrangement and very faint clonal IgH rearrangement were demonstrated, and the diagnosis of angioimmunoblastic T-cell lymphoma was made. Treatment with MOPP was started, followed by Hydroxycarbamide and CHOP but the outcome was fatal. During the evolution, there was no blastic transformation of the chronic myelomonocytic leukemia. The T-cell lymphoma extended to abdominal lymph nodes, Waldeyer ring and bone marrow and the percentage of large LMPI EBER (+) B-cells increased in the lymph nodes. These findings do not support a common stem cell abnormality leading to myelodysplasia in the bone marrow and lymphoma in peripheral lymph nodes. The lack of a clearcut light chain restriction in the EBV infected B-cell is suggestive of a persistant EBV infection in polyclonal or oligoclonal activated B-cells as described in immunodepressed patients. The association of CMML features and an angioimmunoblastic T-cell lymphoma is discussed.