Clinical data: A 62-year-old woman was referred for aspiration cytology. She has been known harboring a thyroid nodule for a year when she underwent on PET CT scan and neck ultrasound because of breast carcinoma. The former did not reveal thyroid abnormality while the latter did it.

Palpation: There was a very firm nodule in the left lobe.

Functional state: euthyroidism with TSH 0.79 mIU/L.

Ultrasonography. The thyroid was echonormal. There was a minimally-moderately hypoechogenic nodule in the ventral part of the left lobe. The lesion presented a somewhat irregular, partly blurred partly lobulated margin.

A suspicious pattern was found on aspiration cytology. Wash-out thyroglobulin resulted in > 478 ug/dL level.

Our final diagnosis was suspicion of thyroid carcinoma.

Histopathology disclosed papillary carcinoma corresponding to the nodule in the left lobe. A focal lymphocytic thyroiditis was also described.

Comment. The tumor' contour presents abutment greater than 50%. Moreover, the capsule of the lobe is discontinuous. Both of these features raised the possibility of extrathyroidal extension. On the other hand, histopathology disclosed that the tumor was clearly within the lobe and has not reached the capsule of the thyroid.