Clinical presentation: A 64-yr-old man was referred for evaluation of a mass in the thyroid which was detected on CT scan. The patient has been operated on laryngeal cancer for several times.

Palpation: a hard, fixed mass in the lower-medial part of the isthmus.

Laboratory tests: TSH 1.26 mIU/L.

Ultrasonography. The thyroid was echonormal. There was a moderately hypoechoic mass in the lower-medial part of the right lobe. The mass had irregular margins and presented with extrathyroidal spread. The left lobe contained a hypoechogenic nodule which showed taller-than-wide sign.

Cytology: anaplastic carcinoma in both lesions. Wash-out thyroglobulin resulted in 0.57 ng/mL and 0.1 ng/mL, right and left mass, respectively.