Preoperative FNA demonstrated atypia of undetermined significance (AUS/Bethesda III) in 13 (50%), suspicious for malignancy (SUS/Bethesda V) in 6 (23%), suspicious for follicular neoplasm (SFN/Bethesda IV) in 4 (15%), benign/Bethesda I in 2 (8%), and malignant/Bethesda VI in 1 (4%).
The association of tumor size with malignancy in thyroid nodules with indeterminate cytology (atypia of undetermined significance [AUS]/follicular lesion of undetermined significance [FLUS], suspicious for follicular neoplasm [SFN]/Hürthle cell neoplasm [HCN], and suspicious for malignancy [SM]) has not been clearly studied.