The role of fine-needle aspiration performed with liquid-based cytology in the surgical management of thyroid lesions.

BACKGROUND: The aim of this retrospective study was to assess the accuracy and usefulness of cytological classification of fine-needle aspirates in determining the appropriate surgical treatment for thyroid lesions studied with conventional smears (CS) and liquid-based cytology (LBC) in a split-sample method. PATIENTS AND METHODS: A total of 353 patients were studied with both CS and LBC. The cytological diagnoses were classified according to the British Thyroid Association into 5 groups: Thy1, inadequate; Thy2, non-neoplastic or benign group including goiter, thyrocytic hyperplasia without nuclear atypia and thyroiditis; Thy3 or indeterminate/follicular proliferation, including follicular neoplasm not otherwise specified and oxyphilic follicular neoplasm; Thy4, suspicious for malignancy, including follicular lesion with nuclear pleomorphism; Thy5, diagnostic for malignancy including papillary carcinoma and medullary carcinoma. The efficacy of thyroid fine-needle aspiration processed by CS with LBC in a split-sample method was evaluated. RESULTS: Overall 164 patients were included in the Thy2, 97 in the Thy3, 49 in the Thy4, and 43 in the malignant Thy5 group. The percentage of unnecessary thyroidectomies decreased from 58.5 to 42% in our series. CONCLUSION: Our subclassification, according to the British Thyroid Association classification, attempts to reduce the number of Thy3 who undergo surgery. The comparison between the traditional management of thyroid lesions and our morphological categories with the use of CS and LBC together allows the number of unnecessary thyroidectomies to be reduced.