Prolonged regression of metastatic leptomeningeal breast cancer that has failed conventional therapy: a case report and review of the literature.

Approximately 5% of breast cancer patients develop leptomeningeal metastases over the course of their disease. Though several treatments options are available for these patients, their prognosis is typically considered to be poor. We report a case of leptomeningeal failure after a patient underwent prior radiotherapy, radiosurgery, surgery, chemotherapy, and biologic therapy. This patient experienced a prolonged response after receiving bevacizumab and capecitabine. The literature currently contains several reports regarding the use of systemic therapy to manage leptomeningeal metastases from breast cancer, which we summarize. Finally, we review the relevant effects of the patient's treatment modalities and provide a rationale for the mechanism that led to her prolonged response.