HER2-Positive Metastatic Breast Cancer — An Interview with Prof Dr Sibylle Loibl on First-Line and Maintenance Therapy

Treatment for HER2-positive metastatic breast cancer has evolved significantly, with modern therapies like T-DXd, tucatinib, and pertuzumab substantially extending overall survival. Professor Sibylle Loibl highlights that while complete responses remain rare—estimated at 5-10%—continuous anti-HER2 therapy and the strategic use of antibody-drug conjugates have transformed the disease landscape. Clinical practice now emphasizes balancing aggressive treatment with quality of life, often transitioning to maintenance regimens like trastuzumab and pertuzumab combined with endocrine therapy to allow for treatment flexibility. Managing toxicities, particularly interstitial lung disease associated with T-DXd and gastrointestinal side effects, remains critical. Future strategies focus on targeting specific mutations such as PIK3CA and exploring the role of exercise and lifestyle interventions to mitigate recurrence risks, aiming to move closer to achieving functional cures for patients.