Clinical presentation: a 61-year-old man was referred for an evaluation of a large nodule in the left lobe. He first noticed a lump 3 years earlier.

Palpation: a hard very large tumor in the region of the left lobe.

Functional state: euthyroidism (TSH-level 0.95 mIU/L).

Ultrasonography: there was a hypoechogenic, inhomogeneous nodule occupying almost the entire left thyroid. The nodule spread substernal. The lesion contained microcalcifications and had irregular borders. The intranodular blood flow was decreased.

Cytological diagnosis: less well differentiated primary thyroid carcinoma.

Histopathology: tall cell variant of papillary cancer.