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

OBJECTIVE: To assess the value of ultrasound in the follow-up of patients undergoing surgery for differentiated thyroid carcinoma. SUBJECTS: The study included 89 patients (70 women and 19 men) with differentiated thyroid carcinoma (76 papillary and 13 follicular cancer). METHODS: 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 I-131, and cervical palpation were evaluated. We determined sensitivity, specificity, and overall accuracy for each of these diagnostic methods. RESULTS: 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 (69%) 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%. CONCLUSION: 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.