BACKGROUND - Certain ultrasound features can predict malignancy in patients with thyroid nodules. The purpose of this study was to determine the value of surgeon-performed ultrasound (SUS) in predicting thyroid malignancy in patients with indeterminate fine-needle aspiration (FNA) cytology.
METHODS - 477 consecutive patients with dominant thyroid nodules were referred to our institution from 2002 to 2007. Of these, 180/477(38%) were judged to have indeterminate cytology: follicular neoplasm (FN, n = 108), Hürthle neoplasm (HN, n = 29), and suspicious for papillary thyroid cancer (SPTC, n = 43). SUS characteristics for thyroid nodules were recorded in a prospective database prior to thyroidectomy. Variables analyzed included patients' age and sex, nodule size, shape, echogenicity, consistency, borders, multiplicity/multicentricity, and presence of microcalcifications. SUS features of thyroid nodules were correlated with final pathology. The accuracy of individual SUS features as well as the presence of two or more adverse features in predicting malignancy was also examined.
RESULTS - There were 144 females and 36 males. Mean age was 52 years (range 17-87 years). Mean tumor size was 2.7 cm (range 0.65-6.6 cm). Overall, final pathology revealed cancer in 92/180 (51%) patients. Malignancy was present in 40/108 (37%) FN, 12/29 (41%) HN, and 40/43 (93%) SPTC. Nodule borders (irregular), shape (height > width), hypoechogenicity, and presence of microcalcifications were significantly associated with malignancy. The presence of 2 or >/=3 adverse SUS thyroid nodule features was associated with a >/=55% or >/=78% risk of malignancy, respectively.
CONCLUSION - Adverse thyroid nodule features seen on SUS may predict malignancy and help determine the initial extent of thyroidectomy in patients with indeterminate FNA cytology.