Clinical and ultrasound features in the management of patients with thyroid nodules indeterminate at cytology: an experience in a large series.

Aims of this study were to evaluate the usefulness of clinical and conventional ultrasound features in the diagnostic work-up of patients with thyroid nodule indeterminate at cytology and to get further insights into the role of real time ultrasonography in the presurgical risk stratification. The study included 1520 consecutive patients with indeterminate cytology who underwent thyroidectomy. The final diagnosis of malignancy at histology was found in 371/1520 (24.4 %) patients. The most frequent histotype was the follicular variant of papillary thyroid carcinoma. Blurred nodule margins (p=0.005) and spot microcalcifications (p=0.003) at thyroid ultrasound (US) and the presence of atypias (Thy 3B) at cytology (p=0.001) were the features more significantly associated with malignancy. At elastosonography a score 1, describing high elasticity, was strongly predictive of benignity, being found in 124 out of 138 (89.8%) benign nodules on histology and in only 4 out of 31(12.9%) with a final diagnosis of carcinoma (p<0.0001) In conclusion we show that thyroid ultrasound is an important tool in the presurgical risk stratification of thyroid cancer in nodules with indeterminate cytology. The inclusion of elastography in the diagnostic work-up greatly increases the predictivity of thyroid ultrasound.