Spanish Breast Cancer Research Group

This study tests a new combination of drugs (alpelisib plus trastuzumab, with or without fulvestrant) against standard chemotherapy for people with a specific genetic mutation (PIK3CA) and a type of advanced breast cancer called HER2-positive. The goal is to see if the new combo …

This study tests whether a combination of two pills (letrozole and abemaciclib) works as well as standard chemotherapy before surgery in women with a common type of early breast cancer (HR-positive, HER2-negative) that is at high or intermediate risk of coming back. About 200 wom…

This study collects information from about 866 women to better understand breast cancer that occurs during pregnancy, breastfeeding, or within a year after giving birth. It also includes women who become pregnant after breast cancer treatment or who used fertility preservation. N…