Fluorine-18-fluorodeoxyglucose positron emission tomography in the preoperative assessment of thyroid nodules in an endemic goiter area

• Published in: Surgery 2003-03, Vol.133 (3), p.294-299
• Main Authors: Kresnik, Ewald, Gallowitsch, Hans Juergen, Mikosch, Peter, Stettner, Haro, Igerc, Isabella, Gomez, Iris, Kumnig, Gerhild, Lind, Peter
• Format: Article
• Language: English
• Subjects: Adenoma - diagnostic imaging; Adult; Aged; Austria - epidemiology; Biological and medical sciences; Carcinoma - diagnostic imaging; Diagnosis, Differential; Endocrinopathies; Female; Fluorodeoxyglucose F18; Goiter, Endemic - epidemiology; Humans; Male; Malignant tumors; Medical sciences; Middle Aged; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Predictive Value of Tests; Preoperative Care; Radiopharmaceuticals; Thyroid Neoplasms - diagnostic imaging; Thyroid Nodule - diagnostic imaging; Thyroid Nodule - pathology; Thyroid Nodule - surgery; Thyroid. Thyroid axis (diseases); Tomography, Emission-Computed - methods
• ISSN: 0039-6060; 1532-7361
• DOI: 10.1067/msy.2003.71

Background. The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in the preoperative assessment of suspicious thyroid nodules. Methods. A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq 18F-FDG. Standard uptake values (SUVs) were calculated. Results. A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. 18F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 ± 2.2, 3.7 ± 1.9, 1.6 ± 0.3, 1.2 ± 0.2, and 0.9 ± 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used. Conclusions. Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. 18F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded. (Surgery 2003;133:294-9.)