Endocrine Abstracts

Introduction: It is unclear whether ultrasonographic (US) findings and fine-needle aspiration biopsy (FNAB) results of nodules accompanied with Hashimoto’s thyroiditis (HT) are affected by the presence of thyroiditis or not. In this study, we compared US features and cytological results of nodules in patients with and without HT.

Methods: Patients who underwent FNAB in our clinic were evaluated prospectively. Nodules in patients with and without HT were categorised as groups 1 and 2 respectively. Cytological results were classified as benign, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS), follicular neoplasia suspicion, malignancy suspicion, malignant, and nondiagnostic.

Results: 181(35.5%) patients with HT and 329 (64.9%) without HT were included in the study. There were totally 800 nodules, 288 (36%) in group 1 and 512 (64%) in group 2. Ultrasonographically, presence of hypoechoic halo and marginal irregularity were similar in two groups (P=0.12 and P=0.20 respectively). Microcalcification was present in 11.8% of nodules in group 1 and 20.3% in group 2 (P=0.002). Macrocalcification was detected in 19.5 and 23.8% of nodules in groups 1 and 2 respectively (P=0.01). 30.6% of nodules in group 1 was hypoechoic, 66.3% was isoechoic, and 3.1% was hyperechoic. In group 2, 40.2% was hypoechoic, 58.4% was isoechoic, and 1.4% was hyperechoic (P=0.01). Solid texture was observed in 78.1% of nodules in group 1 and 62.3% of nodules in group 2 (P<0.001). Cytological results were as follows; in group 1, 78.1% benign, 2.4% AUS/FLUS, 0.3% malignancy suspicion, 1.7% malignant, and 14.6% nondiagnostic; in group 2, 81.4% benign, 2.3% AUS/FLUS, 0.4% follicular neoplasia suspicion, 1.0% malignancy suspicion, 1.4% malignant, and 13.5% nondiagnostic (P=0.78).

Conclusion: Suspicious US features such as microcalcification, macrocalcification and hypoechoic appearance are found with a lower prevalence in nodules accompanying HT. Cytological results were similar in patients with and without HT.