Phase II Study of Systemic High-dose Methotrexate and Intrathecal Liposomal Cytarabine for Treatment of Leptomeningeal Carcinomatosis From Breast Cancer.

Metastatic breast cancer frequently leads to brain metastases and, less commonly, leptomeningeal carcinomatosis (LC). Once cerebrospinal fluid involvement occurs, the prognosis is poor. There are limited treatment options available, but none offer significant survival benefit. Methotrexate, given systemically at high doses (3.5-8 gm/m2), achieves cytotoxic concentrations in the CSF and has been shown to prolong survival in patients with LC. Intrathecal liposomal cytarabine has been shown to increase time to neurologic progression in patients with breast cancer and LC. The combination of these 2 agents in LC has not been studied extensively. Here, we present the results of the phase II study with this combination showing promising efficacy and very good tolerability.