F18-FDG-PET/CT thyroid incidentalomas: a wide retrospective analysis in three Italian centres on the significance of focal uptake and SUV value
- 471 Downloads
Thyroid incidental uptake is defined as a thyroid uptake incidentally and newly detected by imaging techniques performed for an unrelated purpose and especially for non-thyroid diseases. Aim of the study was to establish the prevalence and pathological nature of focal thyroid incidentalomas detected at F18-FDG-PET/CT in patients studied for oncological purposes and not for thyroid disease. Secondary end point was to establish a possible maximum standardised uptake value cut-off over which a malignant lesion should be suspected. We have retrospectively evaluated 49519 patients who underwent F18-FDG-PET/CT for oncologic purposes in three Nuclear Medicine Centres (N.1 = 11278, N.2 = 31076, N.3 = 7165). A focal incidental thyroid uptake was diagnosed in 729 (1.5 %) patients (287–39.4 % male and 442–60.6 % female; average age: 65.26). Of 729 thyroid incidentalomas 211 (28.9 %) underwent further investigation to determine the nature of the nodule; 124/211 (58.8 %) incidentalomas were benign, 72/211 (34.1 %) malignant, 4/211 (1.9 %) non-diagnostic at cytological examination in the absence of surgery and histological evaluation and 11/211 (5.2 %) were indeterminate at cytological examination. A centre-based receiver operating curve (ROC) analysis of the patients with a definitive diagnosis was performed to identify a SUVmax cut-off useful in differentiating benign from malignant incidentalomas. In the centre N.1 it was 4.8 (sensitivity = 95.7 %, specificity = 46.4 %, area under the curve = 0.758); 5.3 in the centre N.2 (sensitivity = 76.3 %, specificity = 72.5 %, area under the curve = 0.815); 7 in the centre N.3 (sensitivity = 57.1 %, specificity = 79.3 %, area under the curve = 0.627). F18-FDG-PET/CT thyroid incidentalomas are a relevant diagnostic reality which requires further investigations and clinical management especially considering that, despite mainly benign, approximately one third of focal thyroid uptakes are malignant.
KeywordsPET/CT F18-FDG Thyroid Incidentaloma
Conflict of interest
The authors declare that they have no conflict of interest.
The authors declare that the experiments comply with the current laws of the country in which they were performed.
- 7.Y.K. Chen, H.J. Ding, K.T. Chen, Y.L. Chen, A.C. Liao, Y.Y. Shen, C.T. Su, C.H. Kao, Prevalence and risk of cancer of focal thyroid incidentaloma identified by 18F-fluorodeoxyglucose positron emission tomography for cancer screening in healthy subjects. Anticancer Res. 25, 1421–1426 (2005)PubMedGoogle Scholar
- 10.T.V. Bogsrud, D. Karantanis, M.A. Nathan, B.P. Mullan, G.A. Wiseman, D.A. Collins, J.L. Kasperbauer, S.E. Strome, C.C. Reading, I.D. Hay, V.J. Lowe, The value of quantifying 18F-FDG uptake in thyroid nodules found incidentally on whole-body PET-CT. Nucl. Med. Commun. 28, 373–381 (2007)PubMedCrossRefGoogle Scholar
- 14.K.W. Kang, S.K. Kim, H.S. Kang, E.S. Lee, J.S. Sim, I.G. Lee, S.Y. Jeong, S.W. Kim, Prevalence and risk of cancer of focal thyroid incidentaloma identified by 18F-xuorodeoxyglucose positron emission tomography for metastasis evaluation and cancer screening in healthy subjects. J. Clin. Endocrinol. Metab. 88, 4100–4104 (2003)PubMedCrossRefGoogle Scholar
- 18.L. Pagano, M.T. Samà, F. Morani, F. Prodam, M. Rudoni, R. Boldorini, G. Valente, P. Marzullo, R. Baldelli, M. Appetecchia, C. Isidoro, G. Aimaretti, Thyroid incidentaloma identified by 18F-fluorodeoxyglucose positron emission tomography with CT (FDG-PET/CT): clinical and pathological relevance. Clin. Endocrinol. 75, 528–534 (2011)CrossRefGoogle Scholar
- 24.K. Ohba, S. Nishizawa, A. Matsushita, M. Inubushi, K. Nagayama, H. Iwaki, H. Matsunaga, S. Suzuki, S. Sasaki, Y. Oki, H. Okada, H. Nakamura, High incidence of thyroid cancer in focal thyroid incidentaloma detected by 18F-fluorodeoxyglucose [corrected] positron emission tomography in relatively young healthy subjects: results of 3-year follow-up. Endocr. J. 57, 395–401 (2010)PubMedCrossRefGoogle Scholar
- 26.H. Hsieh, S. Lin, B. Yang, Y. Chu, C. Chang, R. Liu, The clinical relevance of thyroid incidentalomas detected by 18F-fluorodeoxyglucose positron emission tomography. Ann. Nucl. Med. Sci. 16, 53–58 (2003)Google Scholar
- 28.J.A. Eloy, E.M. Brett, G.M. Fatterpekar, L. Kostakoglu, P.M. Som, S.C. Desai, E.M. Genden, The significance and management of incidental [18F]fluorodeoxyglucose-positron-emission tomography uptake in the thyroid gland in patients with cancer. AJNR Am. J. Neuroradiol. 30, 1431–1434 (2009)PubMedCrossRefGoogle Scholar
- 33.D.S. Cooper, G.M. Doherty, B.R. Haugen, R.T. Kloos, S.L. Lee, S.J. Mandel, E.L. Mazzaferri, B. McIver, S.I. Sherman, R.M. Tuttle, American thyroid association guidelines taskforce. Management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid. 16, 109–142 (2006)PubMedCrossRefGoogle Scholar
- 35.G. Treglia, L. Giovanella, F. Bertagna, D. Di Franco, M. Salvatori, A pooled analysis to calculate the prevalence and risk of malignancy of thyroid incidentalomas detected by fluorine-18-fluorodeoxyglucose positron emission tomography. Thyroid. (2012). doi: 10.1089/thy.2012-0216 PubMedGoogle Scholar
- 38.L. Pagano, M. Caputo, M.T. Samà, V. Garbaccio, M. Zavattaro, M.G. Mauri, F. Prodam, P. Marzullo, R. Boldorini, G. Valente, G. Aimaretti, Clinical-pathological changes in differentiated thyroid cancer (DTC) over time (1997–2010): data from the University Hospital “Maggiore della Carità” in Novara. Endocrine 42, 382–390 (2012)PubMedCrossRefGoogle Scholar
- 41.G. Fadda, F. Basolo, A. Bondi, G. Bussolati, A. Crescenzi, O. Nappi, F. Nardi, M. Papotti, G. Taddei, L. Palombini, SIAPEC-IAP Italian Consensus Working Group. Cytological classification of thyroid nodules. Proposal of the SIAPEC-IAP Italian Consensus Working Group. Pathologica 102, 405–408 (2010)PubMedGoogle Scholar
- 45.A.L. Traugott, F. Dehdashti, K. Trinkaus, M. Cohen, E. Fialkowski, F. Quayle, H. Hussain, R. Davila, L. Ylagan, J.F. Moley, Exclusion of malignancy in thyroid nodules with indeterminate fine-needle aspiration cytology after negative 18F-fluorodeoxyglucose positron emission tomography: interim analysis. World J. Surg. 34, 1247–1253 (2010)PubMedCrossRefGoogle Scholar
- 46.A.D. Bloom, L.P. Adler, J.M. Shuck, Determination of malignancy of thyroid nodules with positron emission tomography. Surgery. 114, 728–734; discussion 734–735 (1993)Google Scholar
- 47.J.C. Mitchell, F. Grant, A.R. Evenson, J.A. Parker, P.O. Hasselgren, S. Parangi, Preoperative evaluation of thyroid nodules with 18FDG-PET/CT. Surgery. 138, 1166–1174; discussion 1174–1175 (2005)Google Scholar
- 48.J.M. Kim, J.S. Ryu, T.Y. Kim, W.B. Kim, G.Y. Kwon, G. Gong, D.H. Moon, S.C. Kim, S.J. Hong, Y.K. Shong, 18F-fluorodeoxyglucose positron emission tomography does not predict malignancy in thyroid nodules cytologically diagnosed as follicular neoplasm. J. Clin. Endocrinol. Metab. 92, 1630–1634 (2007)PubMedCrossRefGoogle Scholar