Role of fine needle aspiration and frozen section in determining the extent of thyroidectomy

The routine use of fine needle aspiration (FNA) and frozen section (FS) in the management of a thyroid nodule is controversial and needs to be evaluated on an institution to institution basis. Our aim was to determine the role of FNA and FS in determining the extent of thyroidectomy. We performed a comparative study of FNA and FS examination of all patients presenting with nodular thyroid disease between September 2002 and December 2005. Data were collected on a proforma by reviewing FNA, FS and histopathological reports. Data were analyzed on SPSS 11. Sensitivity, specificity, accuracy, positive predictive value and negative predictive values were calculated. We included 44 patients with preoperative FNA, intraoperative FS examination and final histopathology reports available. We excluded patients with local invasion and distant metastases. Final histopathological report was taken as gold standard. FNA reported 8 benign, 7 papillary carcinoma, 22 follicular neoplasm, 1 medullary and 6 suspicious lesions. On final pathology there were 16 benign and 28 malignant cases. Thus a total of 20 carcinomas were missed by FNA. When routine FS was done, a total of ten patients who had malignancy were missed. Both FNA and FS have high specificity for diagnosis of thyroid cancer but lacked sensitivity at our institution. This is mainly because of high false negative results.