Sonographically Estimated Thyroid Nodule Malignancy Risk: Strengths and Limitations in Clinical Practice

Abstract

In recent years, the clinical relevance of thyroid ultra-sound has increased. Due to the development of risk-stratification systems that use a systematic assessment of thyroid nodule sonographic characteristics and tiered categories, such as the Thyroid Imaging Reporting and Data System (TI-RADS), a pattern of morphologic features is easily translated into a specific class, with an associated estimate of malignancy risk and suggestions for clinical management. Currently, scientific societies ( 1. Gharib H. Papini E. Garber J.R. American Association of Clinical Endocrinologists, American College of Endocrinology, and Associazione Medici Endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules – 2016 update. Endocr Pract. 2016; 22 (et al): 622-639 Abstract Full Text Full Text PDF PubMed Scopus (802) Google Scholar ) recommend using sonographic risk evaluation to guide clinical decisions regarding the need for fine-needle aspiration cytology and the timing of subsequent follow-up evaluations ( 5. Durante C. Grani G. Lamartina L. The diagnosis and management of thyroid nodules: a review. JAMA. 2018; 319 (et al): 914-924 Crossref PubMed Scopus (318) Google Scholar ). The main aim of these systems is to reduce the burden of diagnostic tests performed on thyroid nodules, namely the number of fine-needle aspirations ( 6. Grani G. Lamartina L. Ascoli V. Reducing the number of unnecessary thyroid biopsies while improving diagnostic accuracy: toward the “right” TIRADS. J Clin Endocrinol Metab. 2019; 104 (et al): 95-102 Crossref PubMed Scopus (157) Google Scholar ), since the majority of nodules (>90%) are benign, and others are small, indolent neoplasms. As a consequence, risk-stratification systems are expected to reduce overdiagnosis and overtreatment.