Figure 1.

H&E stain of cell block preparation of the right paratracheal lymph node (A), revealing solid sheet/nest of malignant cells, some with intracytoplasmic mucin. H&E stain of sections from the right parietal brain tumor (B) revealing malignant cells with large pleomorphic nuclei, frequent multinucleation, and increased mitoses. Tumor cells are positive for cytokeratin 7, TTF-1, and Napsin A (not pictured), supporting metastasis from pulmonary primary origin. The adjacent brain parenchyma has abundant reactive changes including reactive gliosis, chronic inflammation, and patchy hemorrhage. H&E, hematoxylin and eosin.