Brain Metastases

Abstract

Brain metastases are the most common neurologic complication related to systemic cancer. With continued improvements in systemic treatment, the incidence is expected to increase. This article reviews the clinical presentation, pathophysiology, prognostic factors, and treatment of metastatic brain tumors. Brain metastases from systemic cancer are up to 10 times more common than primary malignant brain tumors and are a significant burden in the management of patients with advanced cancer. Common presenting symptoms include headache, focal weakness or numbness, mental status change, and seizure. Management and treatment of metastatic brain tumors is complex and dependent on several factors, including age, performance status, number of metastases at presentation, and status of systemic disease. At the time of diagnosis, most patients have more than one brain metastasis, and treatment has traditionally consisted of whole-brain radiation therapy (WBRT). For those patients with single brain metastases, aggressive local treatment with surgery or stereotactic radiosurgery (SRS) combined with WBRT has been shown to improve survival and neurologic outcomes compared with WBRT alone. In patients with a limited number of brain metastases, SRS alone is being increasingly explored as a treatment option that spares the upfront toxicity of WBRT. Currently, the role of chemotherapy is limited to experimental settings and salvage after radiation therapy. Patients with brain metastases have complex needs and require a multidisciplinary approach in order to optimize intracranial disease control while maximizing neurologic function and quality of life. Patients with multiple metastases, uncontrolled systemic disease, and poor functional status are typically treated with WBRT alone, whereas surgery and SRS may be used for additional local control in a subset of patients with fewer tumors and good functional status. The incorporation of neuropsychological outcomes, neurologic function, and quality of life as end points in future studies will offer further guidance for providing comprehensive care to patients with metastatic brain tumors.