A Comparative Study of the Bethesda System of Reporting of Fine Needle Aspiration Cytology Thyroid with Histopathology


Kirthi Nath K.V.1 , Geetha Sukumaran2

BACKGROUND The Bethesda system of reporting thyroid cytopathology is an outstanding and systematic approach of reporting thyroid cytology samples, thereby reducing the communication gap between cytopathologist and clinician, leading to a better patient care approach. We aim to study the thyroid fine needle aspiration (FNA) using the Bethesda system and evaluate its accuracy taking histopathology as gold standard. METHODS This was a descriptive study including 200 consecutive cases which came to our cytology department between January 2014 and December 2014. All thyroid fine needle aspiration cytology (FNAC) were categorised as per the Bethesda system and followed up with corresponding histopathology. RESULTS Out of the 200 cases, adequacy criteria was met in 196 (98 %) cases. 176 (88 %) cases fell in the benign category, 4 (2 %) cases were inadequate samples, 8 (4 %) showed features of follicular neoplasm / suspicious of follicular neoplasm and 12 (6 %) were malignant lesions. Histopathology follow up was available for all cases. Statistical analysis showed a specificity of 100 % (high), sensitivity of 40 % (low). Positive predictive value was 100 %, negative predictive value was 90.4 %. Accuracy rate was 91 %. CONCLUSIONS Interpreting the thyroid FNAC results using Bethesda system allowed a superior interlaboratory agreement leading to improved clinical management.