Reversible Epstein-Barr virus-negative lymphadenopathy and bone marrow involved by Hodgkin's lymphoma in a rheumatoid arthritis patient undergoing long-term treatment with low-dose methotrexate: a case report and review of the literature.

We report a case of spontaneous regression of Epstein-Barr virus (EBV)-negative methotrexate-associated lymphadenopathy occurring with Hodgkin's lymphoma in the bone marrow of a 48-year-old woman with rheumatoid arthritis. Following 10 years of treatment with low-dose methotrexate, the patient developed pancytopenia, hypercalcemia, and elevated levels of liver enzymes over the course of 2 months. A computed tomography scan of the abdomen revealed splenomegaly and enlarged abdominal lymph nodes. A bone marrow biopsy demonstrated cellular marrow with 2 paratrabecular granuloma-like lesions composed of histiocytes, fibroblasts, small lymphocytes, a few plasma cells, and scattered CD30(+)CD15(+) Hodgkin's cells, including a classic Reed-Sternberg cell. The results of EBV studies of the bone marrow were negative. Within a month from withdrawal of methotrexate treatment, the patient's symptoms and the abnormalities in the laboratory results had regressed completely. A positron emission tomography scan failed to detect lymphadenopathy. Twelve months later, the patient remains free of symptoms.