Figure legends
Figure 1. (a) Initial CT images of the primary lesion replacing the thyroid lobe. (b) Representative CT image of the liver metastasis after lenvatinib treatment. Red arrows indicate the tumor lesions. (c) Low- (upper) and high- (lower) magnification of HE-stained images of the metastatic ITTC. (d) Immunohistochemical staining of CD5, p40, PAX5, and TTF-1 in the metastatic ITTC.
Figure 2. Low- (left) and high- (right) magnification images of PD-L1 immunohistochemical staining on tumor cells within the metastatic ITTC.
Figure 3. (a) Left: separation of different tumor areas on representative image of the metastatic ITTC indicated by block dashed lines. Contour plots of PD-L1+ tumor cells (middle) and PD-1+ T cells (right). (b) Representative HE staining (left) and multiplex IHC (right) images of the metastatic ITTC. Biomarkers and colors are shown on the right side. (c) Gating strategy of PD-1+CD3+CD8+ T cells shown in the image cytometry plots. Subject image is in figure 3a. (d) Frequencies of PD-1-expressing CD3+CD8+ T cells in different tumor areas.