The Role of Histopathology in Diagnosing Thyroid Swellings: Correlation with Clinical, Radiological, Cytological, and Surgical Findings
Arvind Kumar Jain, Mamta Jain, Abhishek Jain, Sakshi Singh, Mayank Sharma, Leena Jain
Author(s)Abstract
Background: Thyroid swellings are one of the most common diagnostic dilemmas in head and neck surgery. The major types of investigative methods used preoperatively include fine-needle aspiration cytology (FNAC) (classified by the Bethesda system) and ultrasonography (USG) risk stratification (ACR TI-RADS). But at times there are discrepancies between the cytological and radiological findings, and the definitive histopathological diagnosis, especially in the indeterminate categories. The objective is to see the level of agreement between FNAC and USG TI-RADS with HPE in thyroid surgery and to study factors associated with discordance. Material and Methods: 220 patients who had thyroid swellings and underwent thyroidectomy were included in the prospective, hospital based observational study over a period of 24-months in a tertiary care centre in Kota, Rajasthan. The agreement between FNAC–HPE was quantified using diagnostic performance metrics (sensitivity, specificity, PPV and NPV) and Cohen's Kappa coefficient. Results: After excluding 15 patients, 205 patients were analysed. FNAC demonstrated a sensitivity of 84.6%, specificity of 92.1%, PPV of 78.5%, NPV of 97.8%, and overall accuracy of 90.7%. The FNAC–HPE agreement was substantial (κ = 0.76). Diagnostic discordance was significantly associated with nodule size > 4 cm and underlying Hashimoto's thyroiditis (p < 0.05). The malignancy rate in Bethesda III/IV lesions was 35.3%. Conclusion: FNAC remains a robust and cost-effective primary screening tool for thyroid nodules; however, integration of ACR TI-RADS risk stratification is critical for the management of indeterminate cytology. Multidisciplinary evaluation combining clinical, sonographic, and cytological parameters is recommended to reduce unnecessary thyroidectomies.
Keywords: Thyroid nodule; Fine-needle aspiration cytology; Histopathology; Diagnostic accuracy; ACR TI-RADS; Bethesda System; Thyroidectomy; Otolaryngology.