A study of ۴۵۰ cases of thyroid nodules and evaluation of diagnostic accuracy of fine needle aspiration

ntroduction: Thyroid nodule is a common disease and although usually benign, malignancy should always be ruled out. Fine needle aspiration (FNA) is the diagnostic modality of choice in approach to thyroid nodules. The main aim of this study is assessment of characteristics of thyroid nodules, risk of malignancy and accuracy rate of FNA in patients in Mashhad.Materials and Methods: We studied ۴۵۰ patients with thyroid nodules during ۲۰۰۳ through ۲۰۰۷ with physical examination, radioisotope scan and FNA. Thyroid surgery performed in ۶۴ patients and histopathology results compared with FNA cytological results. The patients were ۳۸۳ women (۸۵.۱%) and ۶۷women (۱۴.۹%) with mean age of ۳۹.۸±۱۲.۷ years.Results: The mean length of largest diameter of nodules was ۳.۹۷± ۱.۸ and the smallest one was ۳.۲۶±۱.۷ (cm). ۵۹% of nodules were located on right lobe, ۳۶% of them on left lobe and ۵% on isthmus of thyroid. ۲۴.۴% of nodules were cystic. ۳۰.۳% of thyroid nodules were functional or hot and ۶۹.۷% of them were cold in thyroid radioisotope scan. In evaluation of cytological findings of nodules aspirate, ۲۸۸ (۶۸.۶%) were benign, ۲۲(۵.۲%) were malignant, ۹۲ (۲۱.۹%) were follicular lesions, ۱۳(۳%) were suspicious and ۵(%۱.۲) were non diagnostic.Comparison of cytopathologic results before and after surgery showed that FNA in operated patients yielded a sensitivity of ۸۲. ۳%, specificity of ۷۸. ۹%, a positive predictive value of ۷۷.۷%, negative predictive value of  ۸۳. ۳% and accuracy of ۸۰.۵%.

Keywords:

Thyroid nodules , Thyroid cancer , Fine needle aspiration