Solitary cold thyroid nodule: cost-ineffectiveness of ultrasonography.

We reviewed our experience with thyroid sonography of 60 patients with nonfunctioning (cold) solitary thyroid nodules proven by iodine 123 scan. Twenty-two patients had surgery; the remaining 38 had thyroid scan and ultrasound only. In the first group, the echograms did not demonstrate the surgically proven nodules in seven patients (32%). In the second group, the thyroid echograms were reported as negative in 12 patients (32%). Two of these patients had computerized tomography (CT) which confirmed the solitary nodule identified on the 123I scan. As a consequence, we no longer perform or recommend routine thyroid echograms on all scintigraphically cold solitary nodules. We believe that the extra cost of a thyroid echogram is not justified and that the most rational application of thyroid ultrasonography is in assessing the response of a nodule to suppressive hormonal therapy.