[Aspiration cytology of the thyroid]

Fine needle aspiration cytology is a basic type of examination in thyreology today. It is primarily indicated for thyroid node to exclude a malignant tumour. The presence of multiple nodes or of one node only has shown to be indicative of the same amount of risk of a malignant tumour for the patient. Ultrasound characteristics are insufficient for the determination of the nature of the focus and all the existing nodes greater than 10 mm are an indication for puncture. As for other diseases, aspiration cytology is indicated in granulomatose thyreoiditis, while in Hashimoto thyreoiditis it is usually indicated only if a node is present. In addition to clearly benignant and clearly malignant results, large part of cytological conclusions fall within the category of suspicious (unclear) findings. All of them are an indication for histological verification, and the predictive value of the results depends on their type. It is approximately 20% in the case of follicular neoplasia, and preoperative histology is useless. Therefore we mostly opt for hemithyreoidectomy, further procedure depending on the final histological finding.