High-resolution ultrasound associated with aspiration biopsy in the follow-up of patients with differentiated thyroid cancer

Abstract

To assess the value of ultrasound in the follow-up of patients undergoing surgery for differentiated thyroid carcinoma. The study included 89 patients (70 women and 19 men) with differentiated thyroid carcinoma (76 papillary and 13 follicular cancer). High-frequency ultrasound (US) was used in the evaluation of 89 subjects who underwent surgery for thyroid carcinoma. Fine-needle aspiration was performed in cases with positive US. In addition, determinations of thyroglobulin (Tgb) in serum, scintigraphy with (131)I, and cervical palpation were evaluated. We determined sensitivity, specificity, and overall accuracy for each of these diagnostic methods. Ultrasonography was positive in 22 subjects, 16 in the nodal area and 6 in the thyroid bed. Twenty-two subjects received fine-needle aspiration with US control; 13 (59%) of 22 were positive for cancer. The results of the US for detecting neoplastic disease showed a sensitivity of 65%, specificity of 86%, and overall accuracy of 82%. The overall accuracy for scintigraphy was 88% and for Tgb, 91%. We concluded that US can be included in the follow-up protocol for patients undergoing surgery for differentiated cancer of thyroid, as a valuable tool to localize the recurrence. This technique is particularly useful in the evaluation of patients who are found to have elevated Tgb levels.