CD274 and colorectal carcinoma: In primary CRCs, high densities of CD68<sup>+</sup> TAMs at the invasive front were associated with shortened brain metastasis-free survival, whereas neither TAM infiltration nor PD-L1 expression correlated with overall survival.<h4>Conclusion</h4>CRC brain metastases exhibit a distinct, stroma-dominated and M2-polarized TME, consistent with site-specific enrichment of protumoral TAM phenotypes within the cerebral niche.