thousands of women with metastatic breast cancer, which is breast cancer that has spread to other parts of the body, are living in the moment and taking ibrance. ibrance with an aromatase inhibitor is for postmenopausal women or for men with hr+/her2- metastatic breast cancer, as the first hormonal based therapy. ibrance plus letrozole significantly delayed disease progression versus letrozole, and shrank tumors in over half of patients. patients taking ibrance can develop low white blood cell counts, which may cause serious infections that can lead to death. ibrance may cause severe inflammation of the lungs