title: Clinical role of FDG PET/CT for methotrexate-related malignant lymphoma.
abstract: Methotrexate-related malignant lymphoma (MTX-RML) is a type of therapy-related lymphoma, and it often occurs in patients with rheumatoid arthritis. The most distinctive characteristic of MTX-RML is a quick response to withdrawal of MTX. However, because there is a risk of recurrence without a distinctive indicator of disease, close follow-up is needed. We present F-18 2-fluoro-2-deoxyglucose (FDG) postitron emission tomography (PET) or computed tomography (CT) images of MTX-RML along with the characteristic clinical presentation of MTX-RML. FDG PET/CT has the advantage of being able to detect malignant lymphoma in patients who have undergone MTX treatment. After withdrawal of MTX, FDG uptake decreases along with a reduction in the volume of lesions. Although recurrent lesion develops independent to the initial FDG PET/CT findings, FDG PET/CT is useful for early detection of unexpected recurrent lesions. FDG PET/CT allows for the assessment of malignant lymphoma and recurrent lesions in patients who received MTX therapy, which is crucial for the management of MTX-RML.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, National Center for Global Health and Medicine, Shinjyuku-ku, Tokyo, Japan. ryogominamimoto@yahoo.co.jp
authors.forename: Ryogo
authors.initials: R
authors.lastname: Minamimoto
authors.forename: Kimiteru
authors.initials: K
authors.lastname: Ito
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kubota
authors.forename: Miyako
authors.initials: M
authors.lastname: Morooka
authors.forename: Yoko
authors.initials: Y
authors.lastname: Masuda-Miyata
authors.forename: Risen
authors.initials: R
authors.lastname: Hirai
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kitahara
authors.forename: Akira
authors.initials: A
authors.lastname: Tanimura
authors.forename: Shotaro
authors.initials: S
authors.lastname: Hagiwara
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Miwa
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008223:Lymphoma / Q000139:chemically induced* / Q000000981:diagnostic imaging*; D008297:Male; D008727:Methotrexate / Q000009:adverse effects*; D008875:Middle Aged; D011877:Radionuclide Imaging; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging
chemical_list: D019788:Fluorodeoxyglucose F18; D008727:Methotrexate