The relationship between thyroid ultrasonography and cytopathology

Introduction: Thyroid fine needle aspiration biopsy (FNAB) is performed under ultrasound guidance to make a diagnosis. According to EU-TIRADS (European Thyroid Imaging and Reporting Data System) category, the morphologic characteristics of the nodule is described. Histopathological results are classified according to the Bethesda system. In this single centre, retrospective study, to investigate which EU-TIRADS groups had no malignancy as a result of FNAB was aimed. Methods: Ultrasonography findings and pathology reports of the patients whom FNAB was performed at the State Hospital between January 2016 and December 2018 were reviewed. 251 patients (201 female, 50 male) who were over 18 years of age (mean age 52.62 ± 12.29) were included. Ultrasonographic findings were classified according to EU-TIRADS. Distribution of EU-TİRADS categories by Bethesda Classification was shown. Frequency tables, descriptive statistics, Kruskal-Wallis H test, and cross-tabulation were used. The analysis was performed using SPSS 25.0. Ethics Committee approval and written informed consent were obtained. Results: Of the 7 cases in Bethesda group V, which were ‘Suspicious for papillary carcinoma’, 42.9% were in ‘High-Risk Category’in EU-TIRADS and 57.1% were in ‘Intermediate-Risk Category’. No benign cases in EU-TIRADS were in Bethesda IV, V and VI groups. Conclusions: None of the benign cases in EU-TIRADS were found to be in the Bethesda IV-V-VI groups. By carrying out studies with larger number of cases, it can be investigated whether it will be considered safe to follow-up the cases in benign EU-TIRADS group without applying FNAB.