title: Mismatch of F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and Tc-99m pertechnetate single photon emission computed tomography (SPECT) in a euthyroid multinodular goiter.
abstract: Imaging results of F-18 fluorodeoxyglucose (FDG) PET/CT scanning and Tc-99m pertechnetate scintigraphy of the thyroid gland are described and compared with pathology in a patient who was followed after left nephrectomy for renal cell carcinoma diagnosed 10 years earlier. On F-18 FDG PET/CT scanning, a multinodular struma with increased localized F-18 FDG uptake in 4 nodules was seen. Two nodules with increased glucose metabolism appeared normal on Tc-99m pertechnetate scintigraphy. Pathology indicated hyperplastic nodules. High focal F-18 FDG uptake was also seen in a lesion that corresponded with a "cold" nodule on Tc-99m pertechnetate scintigraphy, suggesting malignant disease. However, pathology revealed hyperplastic nodules with a background of aspecific lymphocytic thyroiditis. A fourth nodule with increased F-18 FDG uptake appeared mixed ("cold"/"hot") on Tc-99m pertechnetate scintigraphy. On pathology, a well-differentiated follicular carcinoma was found. These findings, in a single patient, illustrate the wide spectrum of matched and mismatched F-18 FDG and Tc-99m pertechnetate thyroid uptake along with their variable pathologic correlates.
authors.affiliation: Department of Nuclear Medicine, Ghent University Hospital, Gent. ingeborg.goethals@ugent.be
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Goethals
authors.forename: Kris
authors.initials: K
authors.lastname: Mervillie
authors.forename: Oliver
authors.initials: O
authors.lastname: De Winter
authors.forename: Louke
authors.initials: L
authors.lastname: Delrue
authors.forename: Katia
authors.initials: K
authors.lastname: Mekeirele
authors.forename: Hamphrey
authors.initials: H
authors.lastname: Ham
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000175:diagnosis / Q000473:pathology; D000368:Aged; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006044:Goiter, Nodular / Q000000981:diagnostic imaging*; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods; D013670:Sodium Pertechnetate Tc 99m; D013961:Thyroid Gland / Q000000981:diagnostic imaging; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D019788:Fluorodeoxyglucose F18; D013670:Sodium Pertechnetate Tc 99m; D005947:Glucose