EFSUMB Guidelines on Multiparametric Ultrasound Thyroid Nodule Evaluation: PART I

Thyroid nodules are common incidental findings, but only a small proportion of cases are malignant (4-6.5%) or symptomatic. Numerous follow-up examinations and invasive diagnostic procedures, such as fine-needle aspiration, fine-needle biopsies, and thyroidectomies, are performed, leading to potentially costly and time-consuming diagnostic procedures and overtreatment. Most experts and scientific societies (EFSUMB, WFUMB, etc.) encourage the use of multiparametric ultrasound evaluation (MPUS) to improve thyroid nodule characterization due to the continuous technological developments including new ultrasound software (microvascular flow imaging, elastosonography, etc.), contrast media (CEUS), and artificial intelligence (AI). Therefore, the recognition and proper use of new multiparametric ultrasound features of thyroid nodules are essential for minimizing unnecessary interventions and guiding appropriate treatment. The goal of these guidelines is to help initiate use of these features in routine clinical practice. In addition, we analyze the use of MPUS in some emblematic thyroid scenarios, such as cytologically indeterminate nodules, multinodular goiters, and extrathyroidal extension of the malignant nodule, and the usefulness of MPUS as a guide for thyroid biopsy/aspiration and in the staging of cervical lymph nodes. Recommendations based on the level of evidence of the published literature and on the EFSUMB expert group's consensus are given for each question.