Utility of the Clinical and Radiological Features in the Management of Bethesda 3 and 4 Thyroid Nodules

Abstract

Deciding the right treatment strategy for patients with Bethesda 3 and 4 fine needle aspiration cytology (FNAC) reports may be challenging. The reported risk of malignancy (ROM) and those from high-volume institutes may not be identical. The cost of molecular testing and its unavailability for routine use limits its utility in decision-making. In this study, we included all patients diagnosed at our institute with Bethesda 3 and 4 thyroid nodules on FNAC between January 2012 and December 2021. We identified the risk of malignancy for these patients along with other factors that could help identify the possibility of malignancy in these thyroid nodules. We utilised the clinical (C), ultrasound features (U), and the Bethesda category (T) to derive the CUT score and derive a cut-off value beyond which malignancy could be predicted. A total of 359 patients were included in the study. The ROM for the Bethesda 3 thyroid nodule was 77.7% (167/215), and that for the Bethesda 4 thyroid nodule was 76.4% (110/144). On multivariate analysis, nodules taller than wider [0.006, 7.662 (1.806–32.5)], male gender [0.024, 2.359 (1.119–4.976)], and the presence of microcalcification [0.004, 2.328 (1.319–4.109)] were found to be significant for the presence of malignancy in the final histopathology. The CUT score > 8.875 was associated with malignancy in the final histopathology. Various clinical and radiological factors may be useful to identify the nodules harbouring malignancy and facilitate appropriate management. The rate of malignancy in Bethesda 3 and 4 nodules among those who underwent surgery in our cohort was higher.