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  • Review Article
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Advances in the follow-up of differentiated or medullary thyroid cancer

Abstract

The long-term survival of patients with thyroid cancer and the possibility of tumour recurrence up to 30–40 years after the achievement of a disease-free status illustrate the importance of lifelong follow-up in these individuals. This Review discusses the most innovative aspects of follow-up protocols for patients with differentiated thyroid cancer, that is, of papillary or follicular hystotype, and those with medullary thyroid cancer. Particular focus is placed on the relevance of new ultrasensitive assays for thyroglobulin measurement and the option of using recombinant human TSH to stimulate thyroglobulin secretion. Methods to compensate for the loss of diagnostic significance of serum thyroglobulin levels in patients with differentiated thyroid cancer and circulating anti-thyroglobulin antibodies are highlighted, as well as the role of the postoperative calcitonin stimulation test and the clinical relevance of determining the doubling time of calcitonin and carcinoembryonic antigen in patients with medullary thyroid cancer. Moreover, this Review gives some insights into the role of molecular thyroid cancer testing, both for prognostic and for therapeutic purposes. Finally, a general overview of traditional imaging procedures, such as neck ultrasonography, CT, MRI and bone scintigraphy, is provided alongside a comparison with new nuclear imaging tests such as PET.

Key Points

  • 95% of patients with differentiated papillary or follicular thyroid cancer (DTC) and 45–50% of those with medullary thyroid cancer (MTC) survive in the long term

  • However, the probability that these patients will experience tumour recurrence, even after several years in clinical remission, is not negligible

  • Detectable levels of serum thyroglobulin are indicative of persistent or recurrent DTC

  • Thyroglobulin stimulation with exogenous recombinant human TSH is preferable to withdrawal of suppressive levothyroxine therapy, as the latter approach can cause hypothyroidism, which severely affects patients' quality of life

  • The same laboratory, and possibly the same thyroglobulin assay, should be used for the follow-up of a patient with DTC, to account for variations in assay specificity and sensitivity

  • Calcitonin is the most reliable tumour marker for diagnosis and follow-up of MTC; however, carcinoembryonic antigen is a valid marker to determine disease progression

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Figure 1: Algorithm for the follow-up of patients with differentiated thyroid cancer, both papillary and follicular, following total thyroidectomy and radioiodine ablation of postsurgical thyroid remnant.
Figure 2: Standard protocols for administering rhTSH to stimulate serum thyroglobulin, dWBS and 18F-FDG-PET.
Figure 3: Algorithm for the follow-up of patients with medullary thyroid cancer following total thyroidectomy and central neck lymph-node dissection.
Figure 4

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Acknowledgements

Work described in this Review was supported in part by grants from the Ministero della Istruzione Universitaria e Ricerca Scientifica (MIUR), the Associazione Italiana per la Ricerca sul Cancro (AIRC), the Istituto Toscano Tumori (ITT) and the Ministero della Salute, Progetto Ricerca Oncologica RF-CAM 2006353005.

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R. Elisei researched the data and wrote the article. Both authors provided a substantial contribution to discussions of the content. A. Pinchera reviewed and/or edited the manuscript before submission.

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Correspondence to Aldo Pinchera.

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Elisei, R., Pinchera, A. Advances in the follow-up of differentiated or medullary thyroid cancer. Nat Rev Endocrinol 8, 466–475 (2012). https://doi.org/10.1038/nrendo.2012.38

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