Clinical presentation: A thyroid nodule in the dorsal part of the right lobe was diagnosed in a 35-year-old woman on PET CT scan. She was operated on colon cancer metastatisizing to the liver 2 years ago. She has been treated for hypothyroidism for 9 years.

Palpation: Both lobes were moderately firm.

Laboratory tests: TSH 4.17 mIU/L on daily 200 microgram levothyroxine. The aTPO-level was 944 U/mL 3 years ago.

Ultrasound. The thyroid was moderately hypoechogenic and presented several discrete, more hypoechogenic lesions and echonormal areas, as well. Except for the lesion in the dorsal part of the right lobe, the discrete areas did not correspond to nodule in pathological sense. This possibility could not be excluded in the hypoechogenic area in the dorsal part of the right lobe. Nevertheless, the irregular shape and borders stood against a true nodule.

Aspiration cytology of the lesion in question resulted in Hashimoto's thyroiditis.

Comment. The echonormal lesion is probably a nodule in pathological sense while the hypoechogenic areas are unlikely true nodules.