Prognostic factor analysis in patients with brain metastases from breast cancer: How can we improve the treatment outcomes?

Purpose: We conducted this study to analyze clinicopathologic features and treatment outcomes for various treatment modalities in breast cancer patients with brain metastases. Patients and methods: Retrospective analysis was performed using medical records of patients who were diagnosed with metastatic brain tumors from breast cancer. The treatment modalities applied included whole-brain radiotherapy (WBRT), surgical resection, stereotactic radiosurgery (SRS) and systemic treatments such as chemotherapy and endocrine therapy. Results: Among 125 female breast cancer patients with brain metastases, 87.2% had Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-2. The median overall survival (OS) was 6.6 months (95% CI 3.9-9.2). A multivariate analysis using the Cox-regression test identified three risk factors; poor PS (P = 0.023), HER2 positivity (P = 0.013), and no additional systemic treatment (P = 0.006). Those patients who had no risk factors showed outstanding outcome (median OS 49 months). On the contrary, the patients who had all risk factors (poor PS with HER2 positive and did not receive additional systemic chemotherapy) showed dismal prognosis (median OS 2 months). Conclusions: Our new classification according to the suggested risk factors for patients with metastatic brain tumor from breast cancer reflects particular characteristics of each subset of the patients with good prognostic capacity.