Solitary Thyroid Nodule and Cancer

In iodine-deficient countries, goiter is endemic and the incidence of thyroid nodules is high. In the United States where table salt is iodinated, thyroid nodules are clinically detectable in only 4–7% of the general population. An aging population and incidental findings from usage of unrelated radiographic studies have however resulted in a higher prevalence of this endocrine entity. High-resolution ultrasonography, which is being used with increasing frequency to image the neck for a variety of disorders, detects thyroid nodules in 16–67% of unselected patients. In autopsy series, 30–60% of thyroids harbor nodules. Many of these micronodules are less than 1 cm in diameter and are usually not clinically relevant in asymptomatic patients.