Prediction of benignancy of the solitary "cold" thyroid nodule by fluorescent scanning.

A quantitative x-ray fluorescent scanning technique has been used routinely to determine iodine content ratios (ICR) of nodule to normal thyroid tissue in patients with solitary "cold" thyroid nodules. A study of 150 patients with histological diagnoses has shown that an ICR above 0.60 is an excellent indicator of benignancy with a sensitivity of 63% and a specificity of 99%. This technique, in conjunction with careful clinical judgment, can be used to identify those patients that are at low risk for malignancy and can probably undergo conservative clinical management.