Clinical data: a 69-year-old man with signs of vena cava superior syndrome. CT examination revealed a tumor in the right upper lobe of the lung and a mass in the right thyroid.

Palpation: a firm nodule in the lower pole of the right thyroid.

Functional state: euthyroidism with TSH-level 1.99 mIU/L.

Ultrasonography: a hypoechogenic nodule in the lower pole of the right thyroid. The margins of the nodule were irregular.

Cytology: a very cellular picture. Atypical, pleomorphic cells with abundant cytoplasm are located in irregular clusters and occur dissociated.

Cytological diagnosis: cancer corresponding to a metastatic squamous cell cancer.

The patient underwent perthoracal biopsy of the mass in the lung which resulted in poorly differentiated sqamous cell lung cancer.