Clinical presentation: a 67-year-old woman detected a nodule in her thyroid 4 weeks earlier.

Functional state: euthyroidism (TSH 0.69 mIU/L, FT4 12.4 pM/L).

Ultrasonography: a moderately hypoechogenic nodule with a halo sign and perinodular blood flow in the right lobe.

FNAC: resulted in the suspicion of papillary cancer.

Histopathology: disclosed benign, hyperplastic nodule.

Comments:

1. It is a rare example for a solitary nodule displaying a halo sign and perinodular blood flow proved to be not a follicular tumor but a hyperplastic nodule.

2. It may be debated whether the cytological pattern corresponds to category 3 (atypia of unknown significance) or category 5 (suspicion of papillary carcinoma) of the Bethesda system. We preferred the former possibility.