Clinical data: a 41-year-old man with a thyroid nodule known for years. Previous FNAC performed in another hospital disclosed colloid goiter. He noticed that the nodule increased in size in the previous months.

Palpation: a solitary firm nodule in the left lobe.

Functional state: euthyroidism with TSH-level 1.33 mIU/L.

Ultrasonography: a solitary hypoechogenic nodule with central cystic degeneration in the left lobe. The nodule displayed a halo sign and perinodular and intranodular blood flow.

Cytological report: follicular tumor.

Suggestion: surgery.

Histopathology: follicular adenoma.