Fig. 3.

Histopathology. H&E staining at a 100x, b 400x, and c 400x. Findings of the immunohistochemical staining (all 200x) for d brachyury, e INI1, f BRG1, g Ki-67, h PD-1, and i PD-L1. Typical histological features of conventional chordoma with abundant extracellular matrix a, b the area is composed of cohesive sheets of larger epithelioid cells with relatively severe nuclear atypia and pleomorphism. No myxoid stroma is present (c). Diffuse nuclear staining for brachyury (d). Intact INI1 (e) and BRG1 (f) expression. PD-1-positive intratumoral lymphocytes (h). PD-L1-positive tumor cells (i). H&E hematoxylin and eosin; PD-L1 programmed death-ligand 1