ABSTRACT
Objective To evaluate the association of the size of thyroid nodules and the diagnostic value of repeat fine needle aspiration cytology(FNAC) in diagnose of thyroid nodules.Methods One hundred and forty-three thyroid nodules in one hundred and thirty-five patients with repeat FNAC and thyroidectomy were retrospectively analyzed.The nodules were divided into three groups according to the largest diameter(L):GroupA,L＜0.5 cm;GroupB,0.5 cm≤L≤1.0cmandGroupC,L＞1.0cm.Yield of FNACs were divided into six levels according to the classification criteria of the Bethesda system,and Level Ⅰ,Ⅲ,Ⅳ,Ⅴ were defined as the indefinite cytological diagnosis.Results The diagnostic rate of repeat FNAC was obviously higher in group B compared with group A and group C,with significantly statistical difference (P ＜0.05).The risk of malignancy for persistently indefinite diagnostic aspirates after repeat FNAC was significantly reduced with statistical difference from the initial indefinite diagnostic aspirates in group B (P ＜0.05),while there was no statistical difference between group A and group C (P＞0.05).The diagnostic accuracy of repeat FNAC in group B was significantly higher than that in group A(P ＜0.05),but not in group C (P ＜0.05).Conclusions The repeat FNAC has a higher efficiency in those nodules with a largest diameter between 0.5 cm and 1.0 cm,and a repeat FNAC can be suggested.