Clinical presentation: A 41-year-old woman was referred for aspiration of a recurrent cystic nodule. She was first examined one year ago when 14 mL cystic fluid was removed. The nodule did not cause any complaints to the patient.

Palpation: an elastic nodule in the right lobe.

Result of blood test: TSH 3.17 mIU/L.

Ultrasonography. The thyroid was echonormal. There was a central-type cystic nodule in the right lobe. The lesion has partly moderately hypoechogenic, partly echonormal solid parts. There were echogenic figures in the ventral part of the nodule. These might be either microcalcifications or presentation of connective tissue.

16 mL yellow cystic fluid was removed. Aspiration cytology resulted in benign cystic lesion.

Suggestion. Thyroid ultrasound in two years.

Comment. This case illustrates how a spongiform type cyst might evolve from a central-type cystic nodule. See video and longitudinal scans of the right lobe.