Figure legends
Fig. 1 Frontal chest x-ray shows bilateral innumerable nodules with a miliary pattern resembling miliary tuberculosis. No evidence of hilar lymphadenopathy is seen.
Fig. 2 Axial images of non-contrast enhanced computed tomography of both lungs show numerous small lung nodules with a random distribution, and a confluent mass within the right lung, indicating disseminated lung metastasis (a-d).
Fig. 3 FNA biopsy of solid thyroid nodule demonstrates isolated and loose clusters of ovaloid atypical cells.
Fig. 4 Trans-bronchial lung biopsy (TBLB) shows that lung parenchyma is infiltrated by sheets and nests of rather monotonous atypical cells with round to oval nuclei, inconspicuous nucleoli, finely dispersed chromatin and moderate amount of eosinophilic cytoplasm. These cells are strongly positive for CK7 (a) and TTF1 (b) by immunohistochemistry (IHC). Atypical cells exhibit a strong and diffuse positive reaction for CEA (c), chromogranin (d), calcitonin (e) and CD56 (f). IHC for P63, Pax8 and NapsinA did not show a positive reaction.