The Similarities and Differences between Liquid-based and Conventional Methods in Evaluation of Thyroid Fine Needle Aspiration Cytologies

AIMS: Thyroid nodules are one of the most frequent medical issues in endocrinology in our country and around the world. The appropriate evaluation of the nodule is critical in the management of patients. Fine needle aspiration cytology (FNAC) is one of the most accurate tools for evaluating these nodules. Conventional and liquid-based (LB) methods are available for thyroid FNAC. In this paper, we aim to determine the best cytological method for the evaluation of thyroid fine needle aspiration materials. SETTINGS AND DESIGN: Fine needle aspiration (FNA) materials obtained and prepared by conventional and LB methods from 310 patients were evaluated. These slides were compared in terms of 12 cytological parameters in a three-tiered system, and the kappa coefficient was calculated. METHODS AND MATERIAL: Two slides were prepared from FNA samples, and the rest of the material was left in protective solution for LB cytology. Surepath was used as a LB technique. Conventional slides (CS) were left to dry in the air and stained with May Grunwald Giemsa. Slides prepared by two different techniques were compared in 12 cytomorphological parameters, and Kappa coefficients and correlations were calculated. STATISTICAL ANALYSIS USED: Kappa statistics. RESULTS: In comparison of LB and CS, the highest kappa coefficient was in chromatin texture (ĸ:0.738) and inflammatory cells (ĸ: 0.482). On other parameters, fair or poor agreement was observed. CONCLUSIONS: Although there are some superiorities to LB cytology, co-application of these two methods is more favorable in thyroid fine needle aspiration.