Non-invasive Imaging Biomarkers of Thyroid Nodules with Indeterminate Cytology

Stratified by ultrasonography and fine-needle aspiration cytology, indeterminate nodules are lesions with an intermediate risk of being malignant (approximately 25%). Diagnostic resection of half the thyroid gland provides the true nature of these lesions but at the cost of 75% of the patients being futilely operated. In case a malignancy is found, a second surgery to remove the whole thyroid gland is often necessary. Different approaches either on cytological material or using imaging have been investigated to further stratify these lesions. This chapter reviewed biomarkers obtained using conventional as well as artificial intelligence-based non-invasive imaging strategies for the differentiation of thyroid nodules with indeterminate cytology. An overview of the abilities of different tests to differentiate between benign and malignant nodules was provided, taking into account the clinical readiness and cost-effectiveness.