Leptomeningeal metastasis

PURPOSE OF REVIEW: Leptomeningeal metastasis occurs in approximately 3-5% of all patients with cancer. A contemporary literature review of methods of diagnosis and treatment of leptomeningeal metastasis was performed. RECENT FINDINGS: The single most important aspect to diagnosis of leptomeningeal metastasis is considering and pursuing the diagnosis in a patient with cancer and neurological signs and symptoms. Evaluation of leptomeningeal metastasis includes contrast-enhanced brain and spine magnetic resonance imaging (MRI) and a radionuclide cerebrospinal fluid (CSF) flow study if leptomeningeal metastasis-directed therapy is being considered. Treatment often requires involved-field radiotherapy to bulky or symptomatic disease sites as well as intra-CSF and systemic chemotherapy. The use of high-dose systemic therapy may benefit patients with leptomeningeal metastasis and obviate the need for intra-CSF chemotherapy. Intra-CSF drug therapy primarily utilizes one of three chemotherapeutic agents (i.e. methotrexate, cytosine arabinoside and thio-TEPA) administered by a variety of schedules either by intralumbar or intraventricular drug delivery. Novel and increasingly utilized intra-CSF agents in the treatment of leptomeningeal metastasis are targeted monoclonal antibodies such as rituximab and trastuzumab. SUMMARY: Although treatment of leptomeningeal metastasis is palliative with median patient survival of 2-3 months (15% of patients with leptomeningeal metastasis survive 1 year), treatment may afford stabilization and protection from further neurologic deterioration in patients with leptomeningeal metastasis.