Clinical data: a 51-year-old woman with a nodule known for years.

Palpation: a moderately firm nodule in the left lobe.

Functional state: euthyroidism with TSH-level 1.08 mIU/L.

Ultrasonography: a solitary hypoechogenic nodule in the left lobe without a halo sign on gray scale mode. Doppler method disclosed perinodular vascularization.

Cytological report: follicular tumor.

Histopathology: microfollicular adenoma.