Thyroglobulin measurements in washout of fine needle aspirates in cervical lymph nodes for detection of papillary thyroid cancer metastases

Abstract

OBJECTIVE: The aim of this study was to evaluate the accuracy of the measurement of thyroglobulin in washout needle aspiration biopsy (FNAB-Tg) to detect papillary thyroid cancer (PTC) metastases. SUBJECTS AND METHODS: Forty-three patients (51.4 ± 14.6 years) with PTC diagnosis and evidence of enlarged cervical lymph nodes (LN) were included. An ultrasound-guided fine-needle aspiration of suspicious LN was performed, for both cytological examination and measurement of FNAB-Tg. RESULTS: The median values of FNAB-Tg in patients with metastatic LN (n = 5) was 3,419 ng/mL (11.1-25,538), while patients without LN metastasis (n = 38) showed levels of 3.7 ng/mL (0.8-7.4). Considering a 10 ng/mL cutoff value for FNAB-Tg, the sensitivity and specificity was 100%. There were no differences on the median of FNAB-Tg measurements between those on (TSH 0.07 mUI/mL) or off levothyroxine (TSH 97.4 mUI/mL) therapy (3.3 vs. 3.8 ng/mL, respectively; P = 0.2). CONCLUSION: The results show that evaluation of FNAB-Tg in cervical LN is a valuable diagnostic tool for PTC metastases that can be used independent of the thyroid status.

Thyroid nodules and differentiated thyroid cancer: update on the Brazilian consensus

“…Lymph nodes larger than 5 mm must be investigated only when they exhibit micro-calcifications or cystic degeneration or, in the absence of these findings, if they are round and lack an echogenic hilum or are hypervascular based on Doppler results (98,140,(157)(158)(159)(160). FNA is crucial to establish the nature of suspicious lymph nodes; therefore, the biopsied tissue must be subjected to cytological analysis and Tg should be measured in the needle washing fluid (158,160).…”

Clinical impact of thyroglobulin (Tg) and Tg autoantibody (TgAb) measurements in needle washouts of neck lymph node biopsies in the management of patients with papillary thyroid carcinoma

“…We used the value of 10 ng/mL, which is consistent with the majority of published reports (11,14,(20)(21)(22).…”

“…The use of Tg-FNAB is well recognized as a valuable instrument in the examination of suspicious LN metastases (3,4,(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). However, there are limited data regarding factors that may interfere with the diagnostic sensitivity of Tg-FNAB, such as the presence of TgAb in washout fluid samples.…”

“…These results may occur in cases of small or cystic LN metastases, which reflect a lack of tumor cells detected during the FNAB procedure (11). Nevertheless, the use of Tg-FNAB alone has several limitations, and despite being well established as an important tool in the investigation of suspicious LN metastases, Tg-FNAB presents variable results between metastatic and non-metastatic LNs (3,4,(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). This subject has been the topic of recent reviews and meta-analysis studies (12,13).…”

Tuberculous Cervical Lymphadenitis Masquerding as Metastatis From Papillary Thyroid Carcinoma

“…Ultrasound-guided thyroglobulin in washout needle aspiration biopsy (FNAB-Tg) has been shown to be a valuable diagnostic tool adjunct to cytology for evaluation in patients with suspicious cervical lymph node (14).…”