Advanced breast cancer, new treatment reduces risk of death

Some 37,000 Italian women are living with metastatic breast cancer, the most advanced and insidious form of the neoplasm, but thanks to research progress the treatment prospects for these patients are increasing. The latest breakthrough comes from the American society of clinical oncology (Asco) congress in Chicago: a new therapy with a drug-conjugated monoclonal antibody has been shown to reduce the risk of disease progression or death by 38% in patients with low and very low expression of the Her2 protein (Her2-low and Her2-ultralow), of whom there are several thousand in our country every year.

This is shown by data from the phase 3 Destiny-Breast06 study on 866 patients, presented in plenary session at the congress by Giuseppe Curigliano, a member of the Aiom (Italian Association of Medical Oncology) national board. The drug (trastuzumab deruxtecan) belongs to the category of drug-conjugated antibodies, i.e. it consists of an antibody directed against the Her2 receptor, expressed on tumour cells, and a very potent chemotherapeutic agent bound to this antibody.

It has been shown to improve patient survival and has made it possible to avoid subsequent chemotherapy after anti-hormone therapy. In hormone receptor-positive metastatic breast cancer, Curigliano explains, 'after endocrine therapy in the early stages, the standard of care is chemotherapy, which, however, is associated with limited benefit. In the study, patients with Her2-low and Her2-ultralow metastatic breast cancer treated with trastuzumab deruxtecan lived longer without disease progression or worsening compared to standard chemotherapy. These results represent a potential change in the way metastatic breast cancer is classified and treated, and the Destiny study allows us to expand the horizons of treatment to patients previously excluded from the benefits of Her2-targeted therapies."

In Italy, there were 55,900 new cases of breast cancer in 2023. 'Progress in the treatment of this neoplasm in recent years has been very important indeed, and chronicity is a reality for a significant number of patients,' stresses Francesco Perrone, president of Aiom. The results of the Destiny study highlight the importance of accurately determining Her2 status. In this sense, the role of the multidisciplinary team in senology centres is fundamental, especially the collaboration between oncologist and pathologist who carry out the diagnostic tests to define the molecular profile'.

For Saverio Cinieri, president of the Aiom Foundation, 'these long-awaited data suggest that the drug may become a preferred first-line treatment option for patients with this type of metastatic breast cancer'. In January 2023, trastuzumab deruxtecan was approved by the European Commission. The Italian Medicines Agency (Aifa) approved its reimbursability in this indication in December 2023.