Application of Thyroid Imaging Reporting and Data System (TIRADS) guidelines to thyroid nodules with cytopathological correlation and impact on healthcare costs.

Aims: To assess the application of American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS) guidelines and the potential reduction of unnecessary fine-needle aspirate (FNA) and cost savings through examination of cytopathological correlation.

Methods: All ultrasound-guided thyroid FNA performed between December 2017 and July 2019 at our institution were included in this study. Prior to performing each FNA, the nodules were scored according to ACR-TIRADS criteria with subsequent cytology scored according to Bethesda criteria. FNA request forms and preceding diagnostic ultrasound reports were analysed for clinical rationale behind each FNA. Collected data were applied to ACR-TIRADS, American Thyroid Association (ATA) and Korean TIRADS (K-TIRADS) criteria. Rate of reduction of unnecessary thyroid FNA and associated costs were subsequently calculated.

Results: A total of 125 patients and 146 nodules were evaluated. A malignancy rate of 7.5% was obtained. Sensitivity and specificity for detection of malignancy were 75% and 41% for ACR-TIRADS, 91% and 26% for ATA and 92% and 19% for K-TIRADS. Reduction in the rate of unnecessary FNA was most superior for ACR-TIRADS at 54.8%. Based on Australian Medicare Benefits Schedule item codes, a total of $18 452.70 might have been saved over the study period had ACR-TIRADS guidelines been uniformly followed.

Conclusions: This study highlights the strengths and limitations of guidelines in the investigative pathway of thyroid nodules, including superiority of ACR-TIRADS in reducing the rate of unnecessary FNA. Continued education is needed towards application of guidelines among radiologists and referring clinicians, given the potential to reduce unnecessary FNA and achieve economic savings.