Cytomorphological correlation of thyroid lesions with thyroid hormone profile in a tertiary care centre in Assam

Background and aims: Fine Needle Aspiration Cytology (FNAC), combined with ultrasonography and a thyroid function test (TFT), is the mainstay of evaluating thyroid swellings. The American Thyroid Association states that Serum Thyroid Stimulating Hormone measurement should be included in the initial evaluation of thyroid swellings. The Bethesda System for Reporting Thyroid Cytopathology comprises six categories. FNAC and TFT help decide the course of treatment for the patient. In this study, the cytomorphological features of the thyroid lesions are studied, categorized according to The Bethesda system for reporting thyroid cytopathology, and correlated with the thyroid hormone status of the patient. Methods: FNAC was performed on 108 cases of thyroid swellings. Each case was classified according to age and gender, cytological results, and The Bethesda System for reporting Thyroid Cytopathology categories. The cases were also correlated with the results of TFT function tests. Results: Non-neoplastic lesions outnumbered neoplastic lesions, with colloid goitre being the most prevalent. According to the Bethesda System, the cytological majority fell into Category II. Non-diagnostic lesions: 12.0%, benign: 62.2%, Atypia of undetermined Significance: 9.2%, follicular neoplasm:3.7%, suspicious for malignancy: 5.5%, malignant 7.4%. Most cases were determined to be euthyroid based on an analysis of TFT. In category II, abnormal TFTs were most prevalent. In Category V, every patient was euthyroid, but in Category VI, 5/8 cases were hypothyroid, and 3/8 were euthyroid.  However, not a single malignant case was hyperthyroid. Conclusion: FNAC and TFTs can be used for early and accurate diagnosis. It gives explicit management directions, including treatment plan/surgery and follow-up.