Clinical Outcomes of Patients With Bethesda III or IV Cytology on Fine Needle Aspiration of Thyroid Nodules—A Retrospective Study

Abstract

Introduction

The appropriate management strategy for patients with thyroid nodules and indeterminate cytology on fine needle aspiration (FNA) remains unclear, especially in centres where molecular testing is not available. In this retrospective study, we aimed to identify factors predicting the risk of malignancy in these patients.

Materials and Methods

This retrospective study included consecutive patients with thyroid nodules with Bethesda III/IV cytology who underwent surgical management at Hamad Medical Corporation, Qatar, between 01/01/2015 and 30/08/2023. Patients who did not undergo surgical management were excluded. We performed univariate and multivariate logistic regression analysis to assess the factors predicting the risk of malignancy in this population.

Results

Of 449 patients included in the study, the majority were females (72.2%). The mean (SD) age was 43.7 ± 10.7 years. Arab was the most common ethnicity (56.6%), followed by South-Asian (18.9%) and South-East Asian (17.8%). Sonographic features of thyroid nodules were classified as ATA very low in 0.9%, low-risk in 49.1%, intermediate-risk in 42.05% and high-risk in 7.95%. 86.2% had Bethesda III cytology and 13.8% had Bethesda IV cytology. Histopathology of thyroidectomy specimens confirmed malignancy in 179 (39.9%) patients. The malignancy rate in Bethesda III was 37.9%, while in Bethesda IV it was 51.6%. In multivariate logistic regression analysis, ATA intermediate (OR of 1.57 (1.03–2.4); p = 0.03) and high risk (OR of 3.92 (1.81–8.48); p = 0.001) sonographic patterns were predictive of malignancy.

Conclusion

In patients with indeterminate thyroid nodule cytology and in the absence of molecular markers, the ATA sonographic pattern of thyroid nodules can guide decision- making for surgical management vs. surveillance.