INTRODUCTION: Several ultrasound risk stratification systems have been developed mainly with the aim of identifying benign lesions and thereby avoiding unnecessary fine needle aspiration (FNA) cytology. This randomized controlled trial assessed if the use of an ultrasound risk stratification system improved identification of lesions requiring surgical treatment. MATERIAL AND METHODS: This was a multi-centre, unblinded and interventional randomized trial comparing selective and non-selective FNA in Western Sweden. Patients were randomized to either selective cytology according to EU-TIRADS criteria or non-selective cytology. RESULTS: A total of 195 patients were included, 93 in the non-selective group and 102 in the selective group, between February 2022 and December 2023. The frequency of nodules with Bethesda category IV-VI (primary outcome) was higher in the selective group (26% versus 13%, p=0.039). The rate of malignancy (secondary outcome) was similar in both groups; 8% in the selective group versus 5% in the non-selective group. The frequency of patients undergoing cytology was reduced from 83% in the non-selective group, to 71% in the selective group. Considering only patients with at least one nodule yielding EU-TIRADS 3 or higher, cytology was omitted in 7% of patients in the selective group, whereas no cytology was omitted in the non-selective group. CONCLUSION: This randomized controlled trial supports the use of EU-TIRADS to correctly select neoplastic nodules for FNA without missing thyroid cancer. The proportion of patients where FNA can be safely omitted using EU-TIRADS may however be exaggerated, indicating a need for further refinement of risk stratification systems for thyroid cancer diagnostics.
Dahlberg et al. (Tue,) studied this question.