Cervical lymph node thyroglobulin measurement in washout of fine-needle aspirates for diagnosis of papillary thyroid cancer metastases

Abstract

BACKGROUND: Patients with papillary thyroid cancer (PTC) and enlarged cervical lymph nodes (CLNs) are usually assessed by fine-needle aspiration biopsy cytology (FNAB-C). Thyroglobulin (Tg) is frequently detected in washout of fine-needle aspirates (FNA) of these lymph nodes. The aim of this study was to evaluate the accuracy of the measurement of FNAB-Tg in the washout of FNAB in combination with FNAB-C to detect CLN metastases in PTC. METHODS: We retrospectively evaluated 163 surgically proven CLNs. Ultrasound-guided FNAB-C and FNAB-Tg measurements were performed and the ultrasound features were evaluated. RESULTS: The sensitivity, specificity and accuracy of FNAB-C, FNAB-Tg and FNAB-C/FNAB-Tg in diagnosis of metastatic CLNs were 85.7, 87.8 and 71.6%, were 80.5, 87 and 82.8% and were 97.1, 96.3 and 95.7%, respectively. The diagnostic sensitivity, specificity and accuracy of FNAB-C/FNAB-Tg for metastatic CLNs was significantly higher than that of FNAB-C or FNAB-Tg alone (p < 0.01). CONCLUSION: Combined US-guided FNAB-C and FNAB-Tg can improve the accuracy for diagnosis of metastatic CLNs in patients with PTC.