Clinical presentation: A 38-year-old woman was referred for aspiration cytology of a nodule which was discovered by the patient herself a few weeks ago.

Palpation: a large moderately firm nodule in the right lobe.

Hormonal examination indicated euthyroidism with TSH 1.07 mIU/L.

Ultrasonography. The thyroid was echonormal. There was a heterogeneous nodule in the right lobe. The lesion contained roughly equal proportions of echonormal and moderately hypoechoic portions. The nodule had a thin halo and presented perinodular blood flow.

Cytology resulted in follicular tumor. Based on the presence of elongated, atypical follicular cells, we indicated a higher than the usual risk of cancer.

Histopathology disclosed follicular cancer with both capsular and vascular invasion.