Breast cancer brain metastases responding to lapatinib plus capecitabine as second-line primary systemic therapy

Brain metastases (BM) are diagnosed in up to 40% of HER2-positive breast cancer patients. Standard treatment includes local approaches such as whole-brain radiotherapy (WBRT), radiosurgery, and neurosurgery. The landscape trial established primary systemic therapy as an effective and safe alternative to WBRT in selected patients with Her2-positive BM. We aim to further focus on the role of systemic therapy in oligosymptomatic patients by presenting this case report. We report on a 50-year-old patient diagnosed with multiple BM 5 years after early breast cancer diagnosis. As the patient was asymptomatic and had a favorable diagnosis-specific GPA score, she received primary systemic treatment with T-DM1. She achieved partial remission within the brain for eight treatment cycles and then progressed despite stable extracranial disease. As the patient remained asymptomatic and refused WBRT, we decided upon trastuzumab, lapatinib plus capecitabine as second-line therapy. Another partial remission of BM was observed; to date, she has received 11 treatment cycles without any sign of disease progression. In this case, WBRT was delayed by at least 14 months, again indicating the activity of systemic treatment in BM. Apparently, in selected patients, BM can be controlled with multiple lines of systemic therapy similar to extracranial disease. Further investigation of systemic treatment approaches is therefore warranted.