New Frontiers in the Treatment of Patients with HER2+ Cancer and Brain Metastases: Is Radiotherapy Always Useful?

Simple Summary: Brain metastases are a major challenge for patients with HER2+ breast cancer. Traditional treatments, like radiotherapy, can help but often cause severe side effects and may not provide lasting control. Researchers are exploring new, more precise treatments, including antibodies, drug-antibody combinations, and small molecule drugs that can better penetrate the brain. These new therapies have shown promise in clinical trials, helping to control brain tumors more effectively and with fewer side effects than radiotherapy. The goal of this review is to improve treatments for HER2+ breast cancer patients who develop brain metastases, enhancing their survival rates and quality of life. The findings from this research could significantly impact the medical community by offering better alternatives to radiotherapy and improving how brain metastases are managed. This progress could provide new hope for patients facing this challenging condition and potentially transform treatment strategies in the future. Brain metastases (BM) pose a significant challenge in the management of HER2+ breast cancer since almost 50% of patients with HER2+ breast cancer develop brain tumors. The complex process of brain metastases involves genetic mutations, adaptations and mechanisms to overcome the blood–brain barrier. While radiotherapy is still fundamental in local therapy, its use is associated with cognitive adverse effects and limited long-term control, necessitating the exploration of alternative treatments. Targeted therapies, including tyrosine kinase inhibitors, monoclonal antibodies, and antibody–drug conjugates, offer promising options for HER2+ breast cancer patients with BM. Clinical trials have demonstrated the efficacy of these agents in controlling tumor growth and improving patient outcomes, posing the question of whether radiotherapy is always the unique choice in treating this cancer. Ongoing research into novel anti-HER2 antibodies and innovative combination therapies holds promise for advancing treatment outcomes and enhancing patient care in this clinical scenario. This narrative review provides a comprehensive overview of traditional medical treatments, molecularly targeted therapy and investigational agents in the management of HER2+ breast cancer with BM, highlighting the evolving landscape and potential future directions in treatment strategies to improve patient survival and quality of life. [ABSTRACT FROM AUTHOR]