Thyroid gland: US screening in a random adult population.

TLDR

High‑frequency ultrasound of 253 randomly selected adults in Finland was used to screen the thyroid, and fine‑needle aspiration was performed on 30 subjects with detected abnormalities. Thyroid echo abnormalities were found in 27.3 % of participants, increased with age and were more common in women; most lesions were solitary, 70 % of nodules were <1 cm, no malignancies were identified, and the findings support a conservative approach to small abnormalities.

Abstract

High-frequency ultrasound examination of the thyroid was performed in 253 subjects (130 women and 123 men; age range, 19-50 years) that were randomly selected from the population in an area of Finland where goiter is not endemic. Thyroid echo abnormalities were detected in 69 subjects (27.3%). Prevalence of abnormalities increased with age, and women showed more lesions than did men in each of the 3 decades. The abnormality was solitary in 39 subjects (57%), multiple in 15 (22%), and diffuse in 15 (22%). Of the 68 individual nodules, 48 (70%) were smaller than 1 cm in diameter. Anechoic rounded nodules 1-5 mm in diameter were found in 28 subjects. Fine-needle aspiration biopsy was performed in 30 subjects. Cytologic examination revealed no unequivocal malignancies. In eight subjects (3.2%) with a diffuse echo abnormality, cytologic evaluation indicated lymphocytic thyroiditis. It is concluded that the prevalence of small thyroid echo abnormalities in a randomly selected adult population is rather high, a fact that supports use of a conservative approach to these types of findings.