Neoplastic meningitis.

Neoplastic meningitis (NM) is a common problem in neuro-oncology occurring in approximately 5% of all patients with cancer, and is the third most common site of CNS metastases. NM is a disease affecting the entire neuraxis, and therefore clinical manifestations are pleomorphic affecting the spine, cranial nerves, and cerebral hemispheres. Because of craniospinal disease involvement, staging and treatment need to encompass all CSF compartments. Treatment of NM utilizes involved-field radiotherapy of bulky or symptomatic disease sites and intra-CSF drug therapy. The inclusion of concomitant systemic therapy may benefit patients with NM and may obviate the need for intra-CSF chemotherapy. At present, intra-CSF drug therapy is confined to three chemotherapeutic agents (ie, methotrexate, cytarabine, and thiotepa) administered by a variety of schedules either by intralumbar or intraventricular drug delivery. Although treatment of NM is palliative with an expected median patient survival of 2 to 6 months, it often affords stabilization and protection from further neurologic deterioration in patients with NM.