Clinical presentation: A 58-yr-old woman was referred for evaluation of a nodular goiter discovered on screening.

Palpation: no abnormality.

Laboratory test: TSH 0.62 mIU/L.

Ultrasonography. The thyroid was echonormal. There was a hypoechoic nodule in the central part of the left lobe. The nodule had blurred borders and presented small irregularities. The extent of the latter did not reach pathological level.

Cytology resulted in benign lesion.

Comment. This is an example of the potential disagreement among investigators regarding nodule borders. We lack a mathematical definition on irregularities of the margin. I mean that in this case the degree of protrusions does not reach the pathological level.