High-dose intravenous methotrexate in the management of breast cancer with leptomeningeal disease: Case series and review of the literature.

Leptomeningeal metastasis (LM) in breast cancer is associated with significant morbidity and mortality. While there is currently no standard therapy, treatment options include craniospinal radiotherapy, intrathecal chemotherapy and systemic chemotherapy. Craniospinal radiotherapy has not demonstrated improved survival and intrathecal chemotherapy is often poorly tolerated due to associated neurotoxicity.