Metastatic triple negative breast cancer has distinct tumor immune landscape

Metastatic triple-negative breast cancer (TNBC) exhibits increased inflammation and higher expression of checkpoint targets compared to non-TNBC cases, with a paradoxical finding that lower PD-L1 expression is associated with better overall survival. Our findings suggest the need for site-specific metastatic tumor analysis and consideration of immunotherapy in metastatic TNBC treatment.