Evaluation of Thyroid Lesions by Fine-Needle Aspiration Cytology: A Cross-sectional Study

Abstract

Introduction: Thyroid diseases are the most common endocrine disorders treated by physicians in their routine practice. Fine Needle Aspiration Cytology (FNAC) plays a dominant role in managing thyroid lesions. Aim: To determine the utility of FNAC in diagnosing various thyroid lesions and to categorise them according to the Bethesda system of reporting. Materials and Methods: This retrospective cross-sectional study was conducted in the pathology department of a tertiary care hospital from July 1, 2016, to June 30, 2021. FNA specimens obtained from 540 patients presenting with thyroid swelling were analysed, classified using the Bethesda system, and the distribution of cases in each category was studied. Results: The age of the patients ranged from 8 years to 74 years, with a mean age of 41 years. The majority of patients were in their third and fourth decades. There was a female preponderance, with a female-to-male ratio of 11:1. Out of 540 cases, 476 (88.15%) were benign lesions, six (1.11%) were Follicular Lesion of Undetermined Significance (FLUS), 22 (4.07%) were Follicular Neoplasm (FN)/Suspicious for FN, three (0.56%) were suspicious of malignancy, 14 (2.59%) were malignant, and 19 (3.52%) were non-diagnostic/unsatisfactory. Cytohistopathological correlation was performed in 52 benign and nine malignant lesions in this study. The sensitivity of FNAC was 94.7%, specificity was 97.6%, and diagnostic accuracy was 96.7%. Conclusion: FNAC is a rapid and minimally invasive procedure used in preoperative screening to distinguish between benign and malignant thyroid lesions. It has high sensitivity and specificity. The Bethesda system allows for precise cytological diagnosis, standardisation in reporting, improved clinical significance, and leads to the best management approaches.

Keywords

• bethesda system
• colloid goiter
• papillary carcinoma thyroid