The univariate analysis of survival included all available clinicopathologic variables (the histology, grade and expression of ER, PR and HER2 in the primary tumor, phenotype of the primary tumor and BCBM, treatments administered prior to and after BCBM, type of first progression, dominant metastatic site and location of BCBM) and all studied immune parameters (reactive astrocytes (GFAP), TILs (CD4+, CD8, microglia/macrophages (CD68+), PD-1 expression on TILs, and PD-L1 and PD-L2 expression on BCBM). The gene discussed is CD4; the disease is neoplasm.