CYTOMORPHOLOGICAL SPECTRUM OF THYROID SWELLINGS IN A TERTIARY CARE CENTRE: A PROSPECTIVE OBSERVATIONAL STUDY

Introduction: Thyroid swellings are one of the most frequently encountered endocrine problems, with a wide range of underlying causes including benign colloid goitre, thyroiditis, and malignancies. Fine Needle Aspiration Cytology (FNAC) is a widely accepted rst-line diagnostic technique for evaluating thyroid lesions. Its classication under the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) provides a standardized framework for risk assessment and clinical decision-making. Aim & Objective: To evaluate the cytomorphological spectrum of thyroid swellings in a tertiary care centre using FNAC and classify ndings as per TBSRTC. Specic objectives were to: Ÿ Determine the cytological diagnosis of thyroid lesions. Ÿ Classify thyroid swellings as per TBSRTC categories. Ÿ Correlate cytology with available histopathological and radiological ndings. Methodology: A prospective observational study was conducted in the Department of Pathology, S.M.M.H. Medical College, Saharanpur, from November 2022 to November 2024. FNAC was performed on 150 patients presenting with thyroid swellings. Smears were stained using May-Grünwald-Giemsa (MGG) and Papanicolaou stains and interpreted under TBSRTC categories I–VI. Relevant clinical data, thyroid function tests (TFTs), ultrasonography (USG), and histopathological ndings (where available) were correlated. Statistical analysis was done using SPSS v25.0. Result: Out of 150 cases, 138 (92%) were female. The most affected age group was 21–30 years. The most common presentation was neck swelling. FNAC diagnoses included colloid nodular goitre (56%) and lymphocytic thyroiditis (32%). According to TBSRTC, 82% cases were classied as benign (Category II), 8% were non-diagnostic (Category I), and 4.7% as atypia of undetermined signicance (Category III). Histopathological correlation in 27 cases showed strong concordance with cytological diagnosis. Conclusion: FNAC, especially when reported using the Bethesda system, is a reliable, economical, and effective diagnostic tool for evaluating thyroid swellings. The majority of lesions encountered in this population were benign, highlighting the utility of FNAC in reducing unnecessary surgical interventions. Integration with imaging and histopathology strengthens diagnostic accuracy.