For metastatic BC, in pivotal clinical trials conducted in patients with HR-positive IBC-NSTs, combined therapy with a hormonal agent such as an aromatase inhibitor or fulvestrant, and a CDK4/6 inhibitor was shown to yield a significant improvement of the progression-free survival and overall survival compared with hormonal therapy alone [44,45,46,47,48]. This evidence concerns the gene CYP19A1 and inflammatory breast carcinoma.