Clinical presentation: a 30-year-old woman was referred for an evaluation of a nodule detected by the patient herself.

Palpation: the surface of the left lobe was irregular. The consistency of the lump in the left lobe was not different from that of right thyroid.

Functional state: subclinical hypothyroidism with TSH 5.32 mIU/L, FT4 13.9 pM/L, aTPO 79 U/mL.

Ultrasonography: the thyroids were echonormal. There was a hypoechogenic lesion in the ventral part of the left thyroid. It was ambiguous whether the lesion was within or outside the thyroid, although the latter was more likely.

Cytology: benign, probably epidermoid cyst.