Diagnostic accuracy of The Bethesda system for reporting thyroid cytopathology: A Five years Study

Abstract

Introduction: Thyroid nodules are a common clinical problem. It is important to differentiate benign from malignant nodules. Fine needle aspiration is utilized as a preoperative diagnostic technique which is safe, simple and cost effective for triaging patients with thyroid nodules. Methods: The study was conducted at Histopathology department of B.J Medical college, Ahmedabad. It involved period of 5 years patients who presented with thyroid swelling and underwent FNAC and Histopathology. Out of these 1325 cases, 210 patients subsequently underwent surgical excision. Results of final histopathology were correlated with cytologic diagnosis. Results: Histopathologic correlation was done in 210 cases. Out of total 210 cases, 3 cases were diagnosed as Non diagnostic or unsatisfactory,199 cases were diagnosed as Bethesda II and No case was Bethesda III while 4 cases were categorized Bethesda IV and 1 case were Bethesda V and 3 cases were Bethesda VI. The incidence of malignancy in Bethesda categories through were 0%,7.53%, 0%,100%,100% and 100% respectively. Overall accuracy Of FNA cytology was 93.8% with 81.25 % sensitivity and 96.06 % specificity. Conclusion: Our study validated the accuracy of TBSRTC in our setup which is concordant with other studies. Therefore, we recommend routine use of TBSRTC for reporting thyroid cytopathology for initial workup. However, risk of malignancy was found to be significantly high in Bethesda IV, V and VI category to warrant further workup including ultrasound/thyroid scan in addition to repeat FNAC.