Background: The aim of this study was to compare the diagnostic accuracy of fine needle biopsy (FNB) and intraoperative frozen-section biopsy (FS) regarding the surgical management of thyroid nodules.
Methods: A total of 812 patients with solitary nodule or dominant nodule in a multinodular goiter were evaluated. The patients underwent preoperative FNB and intraoperative FS diagnosis.
Results: The definitive histological diagnosis (HD) was: i) 222 malignant lesions (118 papillary, 67 follicular, 16 anaplastic and 8 medullary cancers); ii) 590 benign lesions. FNB accuracy was 90.6%, sensitivity 96.8% and specificity 87.1%. FS accuracy was 97.4%, sensitivity 91.3% and specificity 100%. False negative (FN) were 10 for FNB and 21 for FS. False positive (FP) were 74 for FNB and 0 for FS. FS was less sensitive for the diagnosis of papillary cancer (more FN) and more specific for the diagnosis of follicular thyroid cancers (no FP).
Conclusions: In conclusion, FS is useful in patients undergoing surgery for a thyroid nodule having a "suspicious" cytology. It adds no information in patients with an FNB diagnosis of malignancy and is of limited use in those in whom an FNB benign lesion is diagnosed.