Intraoperative Frozen Section May Reduce the Need for Reoperative Thyroid Surgery in Patients with Follicular Neoplasm

Abstract

Background: Follicular neoplasm (Bethesda IV cytology) requires thyroid lobectomy for diagnosis. Approximately 15-30% of cases are ultimately malignant, requiring reoperative completion thyroidectomy. We sought to reassess whether intraoperative frozen section (FS) reduces the need for reoperative thyroidectomy in these cases. Methods: A retrospective chart review of fine needle aspiration (FNA) results showing follicular neoplasm from 2003 to 2012 was performed. Our practice is to offer thyroid lobectomy with FS for these patients; with suspicious FS, surgery proceeded to total thyroidectomy. FS suspicious for papillary thyroid carcinoma (PTC) was based on nuclear features (nuclear grooves/atypia, pseudo-nuclear inclusions) and for follicular thyroid carcinoma (FTC) was based on capsular/vascular invasion. Results: A total of 148 patients with follicular neoplasm on FNA were identified, of which 79 underwent FS. Fifteen had suspicious FS with 12 having malignancy on final pathology, for a positive predictive value of 80%. Nine showed features suspicious for PTC, of which eight had PTC. Six showed features suspicious for FTC, of which four had malignancy on final pathology. Of the 64 patients with unremarkable FS, 49 had benign final pathology, for a negative predictive value of 77%. Twelve (19%) patients required reoperation. Seven of 19 patients (37%) with malignancy avoided reoperation due to FS. Risk of malignancy with follicular neoplasm diagnosis was 34% (51/148), while risk of malignancy with follicular neoplasm and suspicious FS was 80%. Conclusions: Risk of malignancy with follicular neoplasm and suspicious FS is 80%. FS may avoid reoperative completion thyroidectomy in up to a third of patients. J Curr Surg. 2016;6(1):1-5 doi: http://dx.doi.org/10.14740/jcs286w