title: Factors associated with fluorine-18-fluorodeoxyglucose uptake in benign thyroid nodules.
abstract: Thyroid nodules that exhibit focal uptake of fluorine-18 ((18)F)-fluorodeoxyglucose (FDG) are relatively frequent. Although the clinical features and associated mechanisms of FDG-avid lesions in both thyroid cancer and cytologically indeterminate nodules have been extensively studied, not much information is available on benign nodules. Therefore, in this retrospective study, the clinical, serological, and sonographic features of 15 benign FDG-avid nodules were compared with those of 17 non-avid lesions. Univariate analysis indicated that the FDG-positive and -negative nodules were similar with regard to age, gender, thyroid stimulating hormone (TSH), anti-thyroglobulin antibodies, tumor size, 4 B-mode sonographic findings (i.e., shape, margin, texture, and echo level), and/or elasticity. The presence of intranodular blood flow and the absence of a cystic component were associated with a greater possibility of positive FDG uptake. Multivariate analysis showed that vascularity was the only independent factor predicting FDG uptake. Across a wide range of tumor types, the extent of FDG uptake is positively correlated with tumor perfusion; this observation is consistent with the results of this study, which shows that FDG uptake in benign thyroid nodules is associated with increased vascularity.
authors.affiliation: Department of Internal Medicine 2, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan. kenji26@hama-med.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohba
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Sasaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Oki
authors.forename: Sadahiko
authors.initials: S
authors.lastname: Nishizawa
authors.forename: Akio
authors.initials: A
authors.lastname: Matsushita
authors.forename: Atsuto
authors.initials: A
authors.lastname: Yoshino
authors.forename: Takafumi
authors.initials: T
authors.lastname: Suda
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D016606:Thyroid Nodule / Q000098:blood supply / Q000175:diagnosis* / Q000000981:diagnostic imaging; D018615:Ultrasonography, Doppler, Color
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18