title: Epstein-Barr virus-infected subcutaneous panniculitis-like T-cell lymphoma associated with methotrexate treatment.
abstract: Methotrexate-associated lymphoproliferative disorder (MTX-LPD) is a lymphoid proliferation or lymphoma in patients treated with MTX. We report a case of Epstein-Barr virus (EBV)-positive subcutaneous panniculitis-like T-cell lymphoma (SPTCL) in a 60-year-old Japanese man treated with MTX for rheumatoid arthritis (RA). SPTCL is a rare cytotoxic T-cell lymphoma characterized by involvement of subcutaneous fat mimicking panniculitis. The patient, who had been on MTX therapy for RA, manifested high fever and lumbago. Physical examination showed multiple subcutaneous nodules on the trunk including axillary and inguinal regions. Biopsy of the inguinal nodule showed profuse infiltration of CD8(+) T-cell lymphoma cells in the subcutaneous adipose tissues. A diagnosis of SPTCL was made according to the diagnostic criteria of World Health Organization classification. EBV-encoded small RNA in situ hybridization revealed that the lymphoma cells contained EBV genome. The cells were positive for EBV latent membrane protein 1, but not for EBNA2. After discontinuation of MTX, the nodules regressed spontaneously. Studies have reported that most MTX-LPDs are B-cell type lymphomas and Hodgkin lymphoma. To the best of our knowledge, EBV-positive SPTCL has not been reported in patients receiving MTX. Our case emphasizes the importance of clinical and virological characterization of MTX-associated SPTCL.
authors.affiliation: Department of Microbiology and Infection, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Yuiko
authors.initials: Y
authors.lastname: Nemoto
authors.forename: Ayuko
authors.initials: A
authors.lastname: Taniguchi
authors.forename: Mikio
authors.initials: M
authors.lastname: Kamioka
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakaoka
authors.forename: Makoto
authors.initials: M
authors.lastname: Hiroi
authors.forename: Akihito
authors.initials: A
authors.lastname: Yokoyama
authors.forename: Hideaki
authors.initials: H
authors.lastname: Enzan
authors.forename: Masanori
authors.initials: M
authors.lastname: Daibata
mesh_terms: D001172:Arthritis, Rheumatoid / Q000150:complications / Q000188:drug therapy; D020031:Epstein-Barr Virus Infections; D006801:Humans; D016399:Lymphoma, T-Cell / Q000139:chemically induced / Q000821:virology; D008297:Male; D008727:Methotrexate / Q000009:adverse effects*; D008875:Middle Aged; D015434:Panniculitis / Q000139:chemically induced / Q000821:virology
chemical_list: D008727:Methotrexate