[Improved Outcomes in Advanced Metastatic Breast Cancer]

In stage Ⅳ breast cancer or recurrent breast cancer diagnosed after a curative treatment and later exhibiting distant metastasis, treatment aims are extending overall survival and improving/maintaining quality of life(QOL). The primary focus of treatment is to control systemic tumor volume, and in this regard, the introduction of novel drug treatment by years is expected to contribute to improvement of survival. However for instance, registration cohort data from France diagnosed between 2008 and 2016, categorized by diagnosis year, revealed improvements in survival only in HER2-positive breast cancer, with no such improvements observed in other subtypes. This variation appears to coincide with the introduction of novel anti-HER2 therapy, suggesting the essential need for the introduction of drugs that clearly demonstrate an extension of overall survival. Significant impacts from introduced new drugs have also been observed in other subtypes since 2017, and examining future data may confirm their reflections. Advances not only in drug development but also in cancer/host genome analysis and molecular diagnostics are allowing for more precise treatment selection and treatment changes. Enhancing treatment strategies, including proper local therapies such as surgery and radiation therapy, remains a crucial challenge.