Comparison of the prevalence and sonographic features of thyroid nodules accompanying autoimmune thyroid diseases

Abstract

Introduction: The coexistence of thyroid nodules and autoimmune thyroid disease (ATD) has been widely reported. The aim of our study was to retrospectively evaluate the prevalence and sonographic features of malignancy of thyroid nodules in ATD patients.

Material and methods: We retrospectively analysed data from 500 patients with ATD in our hospital. We recorded ultrasonographic, histopathological and laboratory features of these patients. Thyroid ultrasonography was performed on all the patients, as well as fine needle aspiration biopsy (FNAB) of the thyroid nodule, when required. Patients underwent operations depending on the result of the FNAB.

Results: Of the 500 with ATD (400 female and 100 male; mean age = 42.4 years), 300 (60%) had Hashimoto's thyroiditis (HT) and 200 (40%) presented with Graves' disease (GD). The frequency of thyroid nodules was statistically significantly higher in those with GD (37.8%) than in those with HT (24.3%) (p 〈 0.001). One hundred and forty-nine nodules underwent FNAB (37.8%, 76 out of 200 had GD and 24.3%; 73 out of 300 had HT). The results of the cytological examination were: non-diagnostic cytology, benign, malignant and indeterminate in 19.4%, 73.8%, 2% and 4.5% of the nodules, respectively. When 55 GD and 32 HT patients, on whom total thyroidectomy had been carried out, were evaluated, the incidence of thyroid carcinoma was similar between patients with GD (n = 3, 5.5%) and HT (n = 2, 6.3%) (p 〉 0.05).

Conclusions: We observed that the prevalence of thyroid nodules in patients with GD was higher than patients with HT. However, in general, the characteristics of the nodules and FNAB results were similar in both ATDs.