(0401) American College of Radiology Thyroid Imaging Reporting and Data Systems Institution and Its Effect on Thyroid Surgeries Among Veterans: A 10-Year Retrospective Cohort Study

Introduction: Risk stratification systems (RSSs) have had an increasing role in homogenizing and simplifying thyroid ultrasound reports. The resultant homogeneity has had on unclear effect on clinical practice. The VA Northern California Healthcare System (VA NCHCS) Radiology department adopted the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) in 2018. We aimed to assess what effect the adoption of TI-RADS at VA NCHCS had thyroid surgical practices.

Methods: A 10-year retrospective review of the VA corporate data warehouse (5 years prior to and 5 years after the universal adoption of TI-RADS). Using CPT and diagnosis codes, all thyroid surgeries performed within this time frame were identified. Data was collected on demographics, type of surgery performed, final pathology, staging of malignancy and any incidental findings. Two-sample t test with equal and unequal variances was used for comparative statistics.

Results: A total of 3,985 patients (1,921 pre TIRADS vs 2,064 post TIRADS) and 7,908 thyroid ultrasounds (3,411 pre vs 4,497 post) were identified in our 10-year study period. Subsequently, 2,859 FNAs were performed (1,245 pre vs 1,614 post). A total of 196 surgeries (99 pre vs 97 post) were performed with a decreasing trend in surgeries for benign pathology (63% pre vs 52% post) and an increasing trend in surgeries for malignancy (37% pre vs 48% post). We identified an increase in partial thyroidectomy surgeries for cancer diagnoses (10% pre vs 21% post). Also there was a significant decrease in total thyroidectomies performed for benign pathology (47% pre vs 26% post, p = 0.03 )

Conclusions: After the institution of TIRADs at our single institution, there was a dramatic increase in the number of ultrasounds and FNAs performed, despite near stable thyroid surgical numbers. There was a significant trend towards less-invasive surgical practices. Further studies are recommended to confirm these findings more broadly.