Therapy-related myeloid neoplasm in methotrexate-associated lymphoproliferative disease in a rheumatoid arthritis patient.

Methotrexate (MTX) has been reported as one of the most potent drugs causing other iatrogenic immunodeficiencyassociated lymphoproliferative diseases (OIIA-LPDs). Recently, we experienced a rare case of OIIA-LPDs in a rheumatoid arthritis (RA) patient; a 58-year-old female patient developed high fever and night sweats during MTX and infliximab administration, and the discontinuation of these drugs led to prompt improvement of such symptoms. However, lymphadenopathies and increased serum lactate dehydrogenase levels were observed, and Hodgkin lymphoma-mixed cellularity was diagnosed by bone marrow (BM) examination. ABVD therapy were then administered, resulting in complete remission. After 2 years of ABVD therapy, anemia and thrombocytopenia with monocytosis gradually developed during tocilizumab therapy. BM examination indicated an increased number of monocytes and blasts with multilineage dysplasia, and an abnormal karyotype, inv(11) (p15q22), was detected, suggesting therapy-related myeloid neoplasm (acute myeloid leukemia/myelodysplastic syndrome). Supportive care including hydroxyurea and transfusions was provided; however, following a sudden and marked increase in the white blood cell count, the patient died within a day because of multiple organ failure. To the best of our knowledge, this is the first report of a patient with OIIA-LPDs-RA who developed a therapy-related myeloid neoplasm. 〔J Clin Exp Hematop 54(2) : 137-141, 2014〕