Accuracy of Fine Needle Aspiration Cytology (FNAC) in comparison to histopathological examination for the diagnosis of thyroid swellings

Abstract

Background: Fine needle aspiration cytology (FNAC) is simple, readily available, reliable, time saving and minimally invasive procedure. And because of that it is widely accepted as a diagnostic tool in recent years. histopathological examination of surgically excised thyroid swelling is also one of the accurate way to determine the pathology. However, it requires preparation and long procedure like anaesthesia, hospitalization and sometime even over treatment. Objectives: Primary objective of this study was to evaluate the result of FNAC in diagnosis of various thyroid lesions and correlate the result of FNAC with Histopathological examination in diagnosis of various thyroid lesions. Materials and Methods: A prospective study carried out for duration of two years. Data collected were detailed history of participants, general physical examination and local examination. Investigations like Thyroid function test, Fine needle aspiration cytology and whenever it was possible histopathological examination was done. Correlation of FNAC with histopathological examination was done in those patients. Results: Out of total 150 recruited patients 132 (82%) were female. Common age group of presentation was 21 to 40 years of age with > 60% were presented during this period. Non neoplastic non inflammatory lesions were common (76.67%) with common lesion were colloid goitre (36.67%), benign cystic lesion (10.67%), and adenomatous goitre (10.67%). 15 (10%) cases diagnosed as inflammatory lesion and 15 (10%) were neoplastic lesions. While 5 lesions were remain undiagnosed. Out of 60 correlated cases of FNAC with histopathological examination four were incorrectly diagnosed. The sensitivity of the FNAC found out 85.71% and specificity 96%. While positive predictive value (PPV) was 85.71 % and negative predictive value was 96%. Conclusion: the FNAC could be consider as primary investigational tool for diagnosis and to differentiate thyroid lesions and so for the selection of patients for surgery.