Comparative study of fine needle aspiration cytology and histopathology correlation of various thyroid lesions

Abstract

Patients with anterior neck swelling constitute common problems encountered in the clinical practice. In all age groups, including children, thyroid cancer is the most prevalent endocrine system cancer. Initial diagnostic testing using fine needle aspiration cytology (FNAC) has been found to be quick and cost effective. Therefore, it is widely accepted and more thyroid cases are diagnosed at an early stage, but it is associated with pitfalls due to difference in correlations between FNAC and Histopathological Examination (HPE). The purpose of the study is to compare the results of FNAC with histopathological findings in order to evaluate the diagnostic efficacy of FNAC.The present study was performed over a period of two years in a tertiary care center. Included in the study were 100 cases of thyroid nodule, which underwent FNAC and the post-operative specimens of whom were subjected to histopathological examination. The results obtained by FNAC were compared with histopathological findings.Out of the 100 cases taken for the purpose of the study, 92 were benign whereas 8 were malignant. The cytological and histopathological diagnosis correlated with each-other in 89 cases. A partial correlation between the cytological and histopathological diagnoses was found in 5 cases. In 6 cases the FNAC diagnosis was not correlating with histopathological diagnosis. FNAC revealed a sensitivity of 62.50%, a specificity of 97.83%, an accuracy of 95%, a positive predictive value of 71.43% and a negative predictive value of 96.77%.FNAC of thyroid lesions is thus proved to be a simple, cost effective and accurate method to diagnose and to guide the management of palpable thyroid lesions Thus, we can see that the diagnostic accuracy of FNAC procedure is very high making it a very useful investigation in the work-up of thyroid patients. However final diagnosis and treatment pattern should be based upon histopathology.