1. Introduction Breast cancer (BC) is the most diagnosed and leading cancer in women, with 2.3 million new cases estimated in 2020 [1]. With the increased BC patients’ survival due to the remarkable improvements in early detection and therapies for primary tumour treatment [2], distant organ metastases arise as the foremost concern for BC survivors. In fact, 20–30% of them die of metastatic disease [3], with a less than 30% 5-year survival rate, even with adjuvant chemotherapy [4].
