Sonographic characteristics of thyroid nodules and the corresponding cytological results from the fine-needle aspiration biopsies
Introduction: A major objective of the ultrasound of thyroid nodules is the stratification of the risk for possible malignancy and the selection of nodules for fine-needle aspiration biopsy (FNAB) and cytological examination.
Objective: The objective of this study was to assess the sonographic criteria used in the selection of thyroid nodules for FNAB and to compare them to the cytological reports.
Methods/Design: This was a retrospective study. 155 cases of FNAB of thyroid nodules for the last 3 years were suitable for analysis (147 women and 8 men). The thyroid sonography was performed on a Fukuda-Denshi 5500 device (Fukuda Corp., Japan) with a linear-array transducer 7.5 MHz. The ultrasound-guided FNABs were performed by the free hand technique; smears were fixed and processed according to Pappenheim.
Results: The following ultrasound features suspicious for possible malignancy were reviewed: hypoechogeneity to the surrounding parenchyma (which was the case in 51.6% of the biopsied nodules), spiculated margins (5.2%), blurred margins (48.4%), absence of halo (34.8%), presence of microcalcifications (5.8%), a taller than wide shape (7.7%), and a significant cervical lymphadenopathy (0.6%). 7.1% of all nodules had no suspicious features, 32.2% had only one, 45.8% - two, and 14.8% had three feautures. The cytology reports showed no risk of malignancy in the absence of suspicious features, a 10% risk - if one feature was present, a 16.9% - if two were present, and a 21.7% risk - if three ultrasound features were present.
Conclusion: The studied thyroid nodules had not been optimally selected by ultrasound prior to the FNAB.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector