The value of thyroglobulin in washout of fine needle aspirate from 16 cervical lesions in patients with thyroid cancer

Abstract

Background and objective: Thyroglobulin in the needle washout (Tg-FNA) and cytology of fine needle aspiration (cyto-FNA) are recommended for diagnosis of metastatic lymphadenopathies and recurrence of differentiated thyroid cancer. The objective of this study was to assess the value of these procedures in 16 cervical masses from patients with thyroid cancer of the follicular epithelium (TC).

Patients and methods: The study included six patients with TC and cervical lymphadenopathies evaluated before initial thyroid surgery and 10 patients followed up after TC surgery with cervical lumps discovered. FNA was performed in all 16 masses. Results of cyto-FNA, Tg-FNA and of the combined tests were compared to the final diagnosis of each lesion.

Results: Among 10 lesions proven to be malignant at surgery, cyto-FNA, Tg-FNA and the combination of both allowed for adequate diagnosis in 7, 9, and 10 cases respectively. Among 6 lesions considered to be benign, cyto-FNA was able to confirm diagnosis in 4, was non-diagnostic in one, and was falsely negative in the remaining case, while Tg-FNA was below the established cut-off value (to consider malignancy) in all cases.

Conclusions: In patients with TC and suspect cervical masses, Tg-FNA improved the diagnostic yield of cyto-FNA alone, thus warranting its routine recommendation when FNA is performed. However, universal standardization of the technique and definition of valid cut-off thyroglobulin values (depending on the immunoassay used) above which the lesion should be considered to be malignant are still pending.

Keywords: Cáncer de tiroides; Ecografía; Fine needle aspiration; Lavado de aguja; Local recurrence; Lymph node metastasis; Metástasis ganglionares; Needle washout; Punción-aspiración con aguja fina; Recurrencias locales; Thyroglobulin; Thyroid cancer; Tiroglobulina; Ultrasound.