title: Methotrexate-related lymphoproliferative disorder of the stomach in a patient with rheumatoid arthritis: a case of disease regression after methotrexate cessation.
abstract: We report the case of a 78-year-old woman with methotrexate-related gastric lymphoproliferative disorder (LPD). The patient had a history of rheumatoid arthritis (RA) and had been treated with methotrexate (MTX). Endoscopic examination revealed round elevated lesions in the stomach, and a biopsy specimen showed atypical lymphoid cell proliferation. Immunohistological study found these atypical cells to be positive for L-26 but not for CD3 or EBER. Therefore, we made a diagnosis of MTX-related LPD showing features of diffuse large B-cell lymphoma. Combined positron emission tomography-computed tomography (PET-CT) using 18F-fluorodeoxyglucose (FDG) showed increased avidity in the stomach in addition to slightly increased FDG-avidity in the mediastinum and left chest wall. We decided not to start chemotherapy but to discontinue administration of MTX, with follow-up using endoscopy and PET-CT. The endoscopic examinations after cessation of MTX demonstrated gradual regression of the elevated lesions. PET-CT 6 months after cessation showed no increased FDG avidity in the stomach. While disease regression was observed in the stomach, the other FDG-avid spots remained unchanged on PET-CT. Therefore, we performed chemotherapy as additional therapy. On PET-CT after chemotherapy, the FDG-avid spots remained unchanged for more than 1 year, and we eventually concluded that they were RA-related inflammatory lesions. In patients with MTX-related LPD, cessation of MTX may be a therapeutic option, but careful follow-up and chemotherapy in accordance with the clinical course are essential.
authors.affiliation: Department of Gastroenterology and Hepatology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan. kazike@wine.plala.or.jp.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Department of Gastroenterology and Hepatology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.|Kansai Electric Power Medical Research Institute, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Takefumi
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Asahibashi Ichoka Naika Clinic, 4-2-26 Nishikujyo, Konohana-ku, Osaka, 554-0012, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Department of Gastroenterology and Hepatology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Fujiwara
authors.affiliation: Department of Gastroenterology and Hepatology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Uose
authors.affiliation: Department of Gastroenterology and Hepatology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Someda
authors.affiliation: Department of Hematology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Miyoshi
authors.affiliation: Department of Hematology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Io
authors.affiliation: Department of Hematology, Kansai Denryoku Hospital, 2-1-7 Fukushima, Fukushima-ku, Osaka, 553-0003, Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Nagai
mesh_terms: D000368:Aged; D018501:Antirheumatic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D005260:Female; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000139:chemically induced / Q000175:diagnosis; D008232:Lymphoproliferative Disorders / Q000139:chemically induced* / Q000175:diagnosis; D008727:Methotrexate / Q000009:adverse effects* / Q000627:therapeutic use; D064847:Multimodal Imaging; D009365:Neoplasm Regression, Spontaneous / Q000473:pathology; D049268:Positron-Emission Tomography; D013274:Stomach Neoplasms / Q000139:chemically induced / Q000175:diagnosis; D014057:Tomography, X-Ray Computed
chemical_list: D018501:Antirheumatic Agents; D008727:Methotrexate
keywords: Lymphoproliferative disorder (LPD); Methotrexate (MTX); Rheumatoid arthritis (RA); Stomach