We therefore characterized the compartment-specific architecture and functional orientation of TAMs in brain metastases and matched primary CRCs.<h4>Methods</h4>Immunohistochemical analyses of CD68 (pan-macrophages), CD86 (M1-associated), CD163 (M2-associated), and PD-L1 were performed on tissue microarrays from tumor specimens of 50 patients with CRC brain metastases, including 31 matched primary tumor-brain metastasis pairs. Here, CD86 is linked to neoplasm.