Fig. 1. A 32-year-old woman with conventional papillary thyroid carcinoma that was initially diagnosed as Bethesda category III (atypia of undetermined significance or follicular lesion of undetermined significance) by fine-needle aspiration.

A, B. Ultrasonography (A, transverse; B, longitudinal view) shows an isoechoic solid mass in the right thyroid gland with no suspicious ultrasonographic features (arrows). The pathologic tumor size was 16 mm, and there was no evidence of lymph node metastasis or gross extrathyroidal extension at surgery.