The higher expression of CD8 and FOXP3 were in primary breast tumors than that in oligometastatic sites both in the intratumoral and peritumoral (primary vs oligometastatic tissue: CD8: the intratumoral P=0.031, the peritumoral P<0.001; FOXP3: the intratumoral P=0.039, the peritumoral P=0.012). Here, CD8A is linked to breast neoplasm.