Indeterminate thyroid nodules in the era of molecular genomics

BACKGROUND: Indeterminate thyroid nodules are diagnosed in up to 30% of fine-needle aspirations and the risk of malignancy in these cases are highly variable. Consequently, managing these nodules has been a challenge. While a diagnostic thyroidectomy would help clarify the pathology, there is the risk of developing surgical-related complications for a procedure that may not have been necessary and associated high costs. Genomic testing of indeterminate thyroid nodules may help better guide management. METHODS: We present an unbiased comprehensive review of available molecular testing for classifying indeterminate thyroid nodules, as well as their strengths and limitations, with the objective to allow practitioners to choose the best testing modality for their patients. RESULTS: Molecular testing of these nodules provided a platform to help distinguish benign versus malignant nodules, providing more confidence to rule in or rule out the likelihood of thyroid cancer in indeterminate nodules. CONCLUSION: Genomic testing has evolved to more comprehensive panels to better stratify indeterminate nodules, including Hürthle cell neoplasms and noninvasive follicular neoplasm with papillary-like nuclear features. Understanding the methodology of each available test improves patient care and reduces unnecessary costs.