Role of frozen section associated with intraoperative cytology in comparison to FNA and FS alone in the management of thyroid nodules.
AIMS: The utilization of fine needle aspiration (FNA) biopsy is an accurate and cost-effective method in the diagnosis of thyroid diseases. However, the non-diagnostic cases and cases of suspicious carcinoma remain a dilemma, and in these cases thyroidectomy is usually recommended, even if only 15-20% of these patients really need a thyroidectomy. To avoid unnecessary surgical treatment, frozen section (FS) is usually performed. This method is well recognized, but is not useful for the diagnosis of follicular lesions. Therefore, many authors have tried to increase the specificity and sensibility of intraoperative examination, supporting it with an intraoperative cytological technique (IC). To clarify the role of intraoperative exam (FS and IC), also comparing to FNA, we have reviewed our own experiences. METHODS: In a period covering 6 years (2000-2005), FS was performed in 1,472 cases out of 11,420 total thyroidectomy operations. FS diagnosis and definitive diagnosis, were reviewed and confirmed, moreover, FNA diagnosis and definitive diagnosis were also considered and all intraoperatory cytological slides were reviewed. Diagnostic accuracy was assessed for FNA and FS with or without intraoperative cytology. We compared 1,472 FS diagnoses with their definitive histological diagnosis; 728 FNA out of 1,472 patients with definitive histological diagnosis, and 564 FS associated with IC out of 1,472 patients with definitive diagnosis. RESULTS: The diagnostic accuracy of these three methods were, respectively, 88.8%, 88.8% and 95.7%. CONCLUSION: We can assert that FS associated with IC remains the most accurate technique in the surgical management of thyroid nodules.