Comparative study of aspiration versus non-aspiration fine needle technique in thyroid nodule and its correlation with post-operative histopathological examination

Abstract

Background: Thyroid gland is unique of all endocrine glands because it is the largest, superficial and the only one amendable to direct physical examination. A discrete swelling in one lobe and with no palpable abnormality elsewhere is termed as solitary swelling. Fine needle aspiration cytology (FNAC) is the investigation of choice in solitary thyroid swellings. There is another technique fine needle non aspiration cytology (FNNAC) which avoids aspiration but still permits cytologic review of the swellings which can also be done in thyroid swellings. The objective of the study was to compare and analyze the preoperative efficiency of FNAC vs FNNAC in solitary thyroid nodules and its correlation with post-operative histopathological examination findings.Methods: A total of 72 patients presenting with thyroid nodule in this hospital in BMCRI, Bengaluru during period of January2017 to December2017 underwent both FNAC and techniques. 23 G needles was used for both FNAC and FNNAC. FNAC was performed using needle and a syringe using aspiration. In FNNAC technique the needle held between thumb and fore finger of one hand was gently inserted into the nodule and was moved in different directions. Material entering the needle hub by capillary action was then expressed onto clean glass slides after attaching syringe filled with air to it and smears were prepared. Cases which underwent total/hemi thyroidectomy, the specimen was sent to pathology department in 10% formalin solution.Results: FNNAC produced diagnostically superior samples and less diagnostically inadequate samples than FNAC.Conclusions: As thyroid is a vascular and a colloid organ, in FNAC aspiration gives blood/colloid with less cellular architecture in most of the cases. In FNNAC cellular architecture was preserved with less blood/colloid background which aids in easier cytological diagnosis. Hence FNNAC is a better technique than FNAC in cytological diagnosis of solitary thyroid nodule.