RESUMO
INTRODUCTION: The management of thyroid nodules has been proposed based on US features and information obtained from Fine-Needle Aspiration Cytology (FNAC). In this study, we checked the diagnostic value of ultrasound in comparison with FNAC in probably benign nodules of thyroid. MATERIALS AND METHODS: Patients with thyroid nodules referred to the Radiology department from 2015 to 2020, were classified into five types based on the American College of Radiology/thyroid imaging reporting and data system (TI-RADS) standards. The patients with TI-RADS III-V were examined by FNA biopsy. Subsequently, the collected data of 535 patients having thyroid nodules with TI-RADS III were statistically analyzed. RESULTS: The mean age of the patients was estimated at 46.57. The analysis of TI-RADS III cases examined by the FNA biopsy revealed that 99.1% of the cases were diagnosed with benign lesions. The mean size of benign and malignant nodules was 27mm and 41mm, respectively. There was no significant correlation between the size of the nodules or patients age, and thyroid malignancy (P-values > 0.05). CONCLUSION: There was a very low chance of malignancy (0.9%) in thyroid nodules with thyroid imaging classification of TI-RADS III. Furthermore, no meaningful correlation was observed between the size of the nodules and their malignancy. Therefore, the use of FNAC, based on the current guidelines, on thyroids for nodules larger than 2.5 cm might need to be revised.