**7. Follow-Up: The Gift That Keeps on Giving?**

Current European, British, and American guidelines recommend regular follow-up of DTC after surgery in order to detect early recurrence, supervise TSH suppression, and manage any surgical complications. It is recommended that it be undertaken by a member of the multidisciplinary team according to the established local protocols [3,30,74]. Surgical morbidity after total thyroidectomy adds significantly to the expenses of surgical treatment. Only a few studies have evaluated the cost-effectiveness of different management strategies for vocal fold paralysis and (temporary) hypoparathyroidism [75–77].

Lifelong surveillance with hormone replacement or TSH suppression has a cost, and this is increasing cumulatively as the number of thyroid cancers treated with surgery increases coupled with the progressive improvement in generic life expectancy. The low yield of cancer recurrence in all but the most aggressive forms of thyroid cancer has called into question the value of thyroid cancer follow-up, especially three-monthly followups advocated by some in the first year and the Thyrogen®-stimulated (Sanofi Belgium, Machelen, Flemish Brabant, Belgium) risk stratification [78].

More than 750,000 thyroid cancer survivors are living in the United States today [25,79,80]. Eighty percent of new thyroid cancer patients are under 65 years of age and the 20-year disease-specific survival is over 90%. The cost of the follow-up of 750,000 patients has to be contextualised with thyroid mortality of just 0.4% of all cancer deaths in the United States [81]. The increasing detection of thyroid cancer and the ageing general population suggest that the thyroid cancer follow-up numbers will continue to rise significantly [82]. The current and projected healthcare-related costs attributable to well-differentiated thyroid cancer care have been studied by Lubitz and colleagues [83]. The total estimated costs associated with WDTC care in 2013 exceeded £1.15 billion in the US alone. The initial

treatment including diagnostics, surgery, and adjuvant radioactive iodine (RAI) accounts for £473 million (or 41% of the total annual costs), and an alarming, £428 million (37% of total costs) is taken by the management of the follow-up. There are also hidden costs related to medical practitioner activity and the cost to society as workdays are lost to attend for investigations and doctor visits are not calculated in this budget calculation.
