[Resected Cases of Thyroid Tumor Diagnosed Class Ⅲ by Fine Needle Aspiration Cytology]

We describe 14 resected cases of thyroid tumor diagnosed as Class Ⅲ by fine needle aspiration cytology(FNA). Of these, 13 cases were diagnosed as: malignant tumor(1 case), suspicion of malignant tumor(5 cases), or were hard to distinguish from benign or malignant(7 cases). The operative methods used were total or near total thyroidectomy plus D1 or D2a in 4 cases; hemithyroidectomy plus D1 in 3 cases; subtotal thyroidectomy in 3 cases; and lobectomy of the thyroid in 4 cases. The final pathological diagnoses were papillary adenocarcinoma(6 cases, all were pStage Ⅰ), follicular adenocarcinoma(1 case, pStage Ⅲ), malignant lymphoma(1 case), follicular adenoma(2 cases), and adenomatous goiter(4 cases). The results of preoperative examination and intraoperative frozen section diagnosis did not accord with the final pathological results in 2 cases(follicular adenocarcinoma: 1, adenomatous goiter: 1). FNA Class Ⅲcases should be treated surgically, because 8 of 14 FNA Class Ⅲ cases were malignant thyroid tumor. The operation method should be selected cautiously.