To summarize, phosphoflow cytometry studies in breast cancer patients have revealed that impaired activation of cytokine signaling pathways, such as IL-6-induced p-STAT1 and p-STAT3 in peripheral T cells, and lower IFN-γ-induced p-STAT1 in peripheral monocytes, are associated with increased risk of relapse. This evidence concerns the gene IFNG and breast carcinoma.