It is devastating when you or someone in your family received the news about metastatic breast cancer, those commonly known as metastatic HER2-positive tumors, an extremely aggressive type of breast cancer.

HER2-positive breast cancer cells express a protein called human epidermal growth factor receptor 2 (HER2), which is involved in promoting tumor growth. In this type of cancer, the gene coding for HER2 is expressed in multiple copies, causing the overexpression of HER2 and consequently, driving tumor growth.

Although in general HER2-positive tumors respond quite well to the current therapies, metastatic HER2 breast cancers have a bad prognosis. The survivorship at this stage has always been really low but, the expectations of novel therapies were in the horizon.

Finally, Dr. Javier Cortés, the director of the International Breast Cancer Center (IBCC), has made an enormous contribution performing a study just published in the New England Journal of Medicine, in which he has combined trastuzumab and deruxtecan. This combination has obtained a disease-free survival of more than 75% after 1 year (vs. 34,1% under the standard regime) and has achieved a 97% patient survival when comparing to standard treatment (86%). Furthermore, the tumor was completely eliminated in 16% of the cases. Luckily, treatment-associated toxicities are standard for these types of treatments, i.e., pneumonitis, which can be easily control with a corticoid regime.