496 chapter 13 Summary of aim of this thesis In the era where de-escalation is one of the keywords in the management of thyroid nodules and differentiated thyroid carcinoma, a lot of attention is also paid to optimization of the diagnostic workup of cytologically indeterminate thyroid nodules, defined as Bethesda III (AUS) or Bethesda IV (FN, including oncocytic type). Chapters 2 and 3 of this thesis showed that the diagnostic possibilities are infinite and that technical innovations are ongoing in the rapidly growing field of imaging and molecular biomarkers. Is the sky the limit? The accurate diagnosis and management of indeterminate thyroid nodules often remains challenging, especially when considering cost-utility and feasibility aspects. It is well known that clinical utility of a diagnostic depends on insuperable global variations in a wide range of epidemiological and economic factors, such as the rate of malignancy, balance of various types of indeterminate cytology in the local case-mix (including the rate of oncocytic cytology, Chapters 4, 11 and 12, among others), and the mutational burden (such as the proportion of BRAF-mutated papillary thyroid carcinoma, Chapter 2), accessibility to and known intra- and interobserver discordance between various diagnostics, and the costs of a test and all other links in the health care chain [26, 30-32]. Globally varying health care costs directly affect cost-utility estimates causing different diagnostics to be cost-effective in different health care systems [25, 28]. In addition, less tangible factors such as local multidisciplinary expertise, compatibility with the ingrained everyday clinical practice and its logistics, global differences in societal norms and values, and the rise of informed shared decision-making that vocalizes the rational as well as the more emotional physician and patient preferences may be of greater influence than one may hope. Some of these factors are of increasing importance in current times, causing worldwide challenges for clinical practice. This thesis investigated the efficacy of [18F]FDG-PET/CT in the preoperative workup of indeterminate thyroid nodules and evaluated the impact of [18F]FDG-PET/CT-driven management to avoid unbeneficial patient management, primarily to reduce the rate of futile diagnostic surgeries for benign nodules. The main results of the EfFECTS trial showed that an [18F]FDG-PET/CT-driven diagnostic workup may avoid nearly half of the unbeneficial diagnostic surgeries for benign non-oncocytic nodules, cost-effectively and with sustained health-related quality of life (HRQoL) (Chapters 4, 6 and 7 of this thesis). Pending further external validation, semi-quantitative assessment of [18F]FDG-PET/ CT may also avoid up to one in three unbeneficial surgeries in benign oncocytic nodules (Chapter 5). In Chapter 12 of this thesis, we finally demonstrated that [18F]FDG-PET/CT and molecular diagnostics (MD) are both accurate rule-out tests in indeterminate nodules, although clinical utility of their combined use is likely limited.
RkJQdWJsaXNoZXIy MTk4NDMw