title: Atypical lymphoplasmacytic and immunoblastic proliferation from rheumatoid arthritis: a case report.
abstract: A case of atypical lymphoplasmacytic and immunoblastic proliferation (ALPIBP) in the lymph nodes associated with well-documented rheumatoid arthritis (RA) is presented. A 68-year-old Japanese female with a 6-year history of RA presented with right neck lymphadenopathy of 3 months duration. A biopsy specimen showed paracortical hyperplasia and numerous lymphoid follicles. On high-power field, the paracortical area was diffusely infiltrated by a polymorphous population consisting of numerous mature plasma cells, plasmacytoid cells, immunoblasts, including Hodgkin-like cells, small- to medium-sized lymphocytes, and histiocytes. Immunohistochemical study demonstrated that immunoblasts usually were CD20+, and a portion of them was CD30+. The histomorphological findings of the present case are similar to those of methotrexate (MTX)-induced atypical lymphoproliferative disorders (LPDs) in some aspects. However, Epstein-Barr virus-encoded small RNA-positive cells were not identified by in situ hybridization. The polytypic nature of B lymphocytes also was demonstrated by immunohistochemistry and polymerase chain reaction. Moreover, there was no history of MTX therapy in the present case, indicating that MTX-induced, LPD-like ALPIB may occur even in the RA patients not treated with MTX therapy.
authors.affiliation: Department of Pathology and Clinical Laboratories, Gunma Cancer Center Hospital, Ohta 373-8550, Japan. mkojima@gunma-cc.jp
authors.forename: Masaru
authors.initials: M
authors.lastname: Kojima
authors.forename: Tadashi
authors.initials: T
authors.lastname: Motoori
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hosomura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Sakata
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Masawa
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications*; D014408:Biomarkers, Tumor; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects; D008206:Lymphatic Diseases / Q000139:chemically induced* / Q000209:etiology* / Q000473:pathology; D008727:Methotrexate / Q000009:adverse effects*
chemical_list: D014408:Biomarkers, Tumor; D007166:Immunosuppressive Agents; D008727:Methotrexate