Clinical presentation: A 43-year-old woman was referred for follow-up examination. We met the patient for the first time 13 years ago when a hypoechogenic lesion was found on ultrasound examination. The dimensions of the lesion were 7x7x9 mm, width x depth x length, respectively. A repeat ultrasound was suggested in 5 years.

Palpation: no abnormality.

Functional state: euthyroidism (TSH 0.67 mIU/L, anti-TPO 8 U/mL).

Ultrasonography. The thyroid was echonormal. There was a minimally hypoechogenic lesion in the upper, ventro-lateral part of the right lobe. The lesion had numerous microcalcifications. The dimensions of the nodule were 9x12x13 mm, width x depth x length, respectively, it means that the volume of the lesion increased by more than 200% in the past 13 years.

Cytology resulted in papillary carcinoma.

Histopathology disclosed papillary carcinoma in the right lobe.

Comment. Although more than 50% of the borders of the nodule are ill-defined, this is partly caused by the improper fitting of the focus, therefore this blur cannot be considered as pathological.