Endocrine Abstracts

The aim of this study was the assessment of diagnostic utility of fine-needle aspiration biopsy needle washout fluids (FNAB-Tg) in the cases of thyroid carcinoma recurrence and analysis of false-positive and false-negative results.

Methods: Two hundred and fifteen FNAB-Tg samples from 201 patients with a history of differentiated thyroid carcinoma with suspicious lymph nodes were included in analysis. The wash-out of needle rinsed with 0.5ml of normal saline solution, using electrochemiluminescence method -ECLIA were performed.

Results: In 64 patients elevated FNAB-Tg levels correlated with positive cytology result. In 13 patients there were no correlation between elevated FNAB-Tg level and cytology result. Four of these patients had cystic metastasis of papillary carcinoma. Nine patients with metastases had not elevated FNAB-Tg levels. In four of them, FNAB revealed carcinoma cells from other malignancies. Three of patients had metastases of dedifferentiated thyroid carcinoma and two had differentiated thyroid carcinoma.

Conclusion: FNAB-Tg of the lymph nodes increases accuracy in the diagnosis of thyroid carcinoma recurrence, especially in detecting of cystic variants and micrometastases or in coexisting malignances of other origin. False-negative FNAB-Tg results may occur in the cases of dedifferentiated thyroid carcinomas or with high serum anti-Tg antibodies.