This is an open-ended prospective registry. The patients who were diagnosed with thyroid nodules will have a complete clinical and US evaluation. Thyroid nodule biopsy indication and FNA vs core biopsy choices will be made entirely on the clinical grounds, by the managing physicians. Thyroid nodule biopsies may be performed at a participating medical or surgical endocrinology office. Following standard cytologic examination a molecular testing using Thyroseq will be performed.