@article {de Geus-Oei770, author = {Lioe-Fee de Geus-Oei and Gerlach F.F.M. Pieters and Johannes J. Bonenkamp and Aart H. Mudde and Chantal P. Bleeker-Rovers and Frans H.M. Corstens and Wim J.G. Oyen}, title = {18F-FDG PET Reduces Unnecessary Hemithyroidectomies for Thyroid Nodules with Inconclusive Cytologic Results}, volume = {47}, number = {5}, pages = {770--775}, year = {2006}, publisher = {Society of Nuclear Medicine}, abstract = {Fine-needle aspiration biopsy (FNAB) is inconclusive in up to 20\% of patients with solitary thyroid nodules. In these cases, hemithyroidectomy is necessary, but only 20\% of the nodules prove to be thyroid carcinoma. The aim of this study was to explore the potential of 18F-FDG PET to reduce the number of unnecessary hemithyroidectomies in the preoperative assessment of thyroid nodules with inconclusive FNAB results. Methods: Forty-four consecutive patients, scheduled for hemithyroidectomy because of inconclusive FNAB findings, participated in this prospective study. 18F-FDG PET of the thyroid region was performed before hemithyroidectomy, and standardized uptake values were calculated. The final histopathologic diagnosis served as a standard of reference. Results: Histopathologic examination of the surgical specimens revealed 7 well-differentiated thyroid carcinomas in 6 patients, all accumulating 18F-FDG (negative predictive value, 100\%). 18F-FDG accumulated in 13 of 38 benign nodules. The pre-PET probability for cancer in this study population was 14\% (6/44), and the post-PET probability increased to 32\% (6/19). The percentage of unnecessary hemithyroidectomies in a hypothetical algorithm using 18F-FDG PET was only 30\% (13/44), compared with 86\% (38/44) without 18F-FDG PET. 18F-FDG PET reduced the number of futile hemithyroidectomies by 66\% (25/38) (95\% confidence interval, 49\%{\textendash}80\%; Fisher{\textquoteright}s exact test, P = 0.0038). Semiquantitative analysis using standardized uptake values did not help to further reduce this number. Conclusion: In addition to data in the literature demonstrating accurate detection of thyroid cancer by 18F-FDG PET, this study showed that 18F-FDG PET should play an important role in the management of patients with inconclusive cytologic diagnosis of a thyroid nodule. 18F-FDG PET reduced the number of futile hemithyroidectomies by 66\%. Although PET is a relatively costly procedure, this cost outweighs the costs and risks associated with unnecessary thyroid surgery.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/47/5/770}, eprint = {https://jnm.snmjournals.org/content/47/5/770.full.pdf}, journal = {Journal of Nuclear Medicine} }