TITLE:
Findings of 18F-Fluorodeoxyglucose Positron-Emission Tomography in Methotrexate-Related Lymphoproliferative Disorder
AUTHORS:
Atsushi K. Kono, Kazuhiro Kitajima, Hiroshi Mmatsuoka, Kyoko Otani, Tomoo Itoh, Kazuro Sugimura
KEYWORDS:
Fluorodeoxyglucose (FDG) F 18, Lymphoma, Methotrexate, Positron-Emission Tomography (PET), Rheumatoid Arthritis
JOURNAL NAME:
Open Journal of Radiology,
Vol.4 No.4,
November
7,
2014
ABSTRACT: Introduction: The use of methotrexate (MTX) for rheumatoid arthritis (RA) is increasing. However, the immune suppression state leads to the occurrence of lymphoproliferative disorder (MTX-LPD). The purpose of this study was to describe the findings of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in MTX-LPD patients, and compare it with non-MTX-related malignant lymphoma (ML). Materials and Methods: We retrospectively reviewed 11 MTX-LPD patients (9 female, mean age 68.3 years) and 21 ML patients (7 female, mean age 60.6 years) with a histopathological diagnosis. FDG-PET imaging was performed using a standard oncology procedure. We assessed the disease distribution based on FDG-PET images and measured the maximum standardized up take values (SUVmax) for each region. Results: Mean values of SUVmax in MTX-LPD and ML were 14.6 and 17.2, respectively (p = 0.49). In MTX-LPD, 55 lesions met the Cotswold classification, consisting of 37 nodal and 18 extranodal lesions. In ML, 82 lesions were found, consisting of 68 nodal and 14 extranodal lesions. MTX-LPD showed a higher incident of the involvement in extranodal lesions throughout the whole body (p