Neoplastic meningitis

Neoplastic meningitis refers to infiltration of the meninges by tumor cells. It affects approximately 5% of all patients with cancer. Based on the origin of the primary tumor, the condition may be categorized as carcinomatous, lymphomatous, or leukemic meningitis. Some clinical features are secondary to elevated intracranial pressure and include headaches, papilledema, and altered mental status. Treatment depends on primary tumor type and the extent of the disease. However, as neoplastic meningitis is usually a sign of advanced disease with systemic spread, the overall prognosis is poor.

• Metastatic infiltration of the meninges by cancer cells from a primary tumor
  • ∼ 5% of patients with neoplasias
• Depending on the origin of the tumor, neoplastic meningitis can be classified as:
  • Carcinomatous meningitis: solid tumors (e.g., lung or breast cancer) Carcinomatous meningitis
  • Lymphomatous meningitis: lymphoma (e.g., non-Hodgkin lymphoma)
  • Leukemic meningitis: leukemia (e.g., acute leukemias)

References:^[1][2][3][4]

• Meningism
• Cranial neuropathies
• Headache
• Papilledema
• Nausea, vomiting
• Altered mental status (ranging from confusion to lethargy)
• Seizures

References:^[2]

• Gadolinium-enhanced MRI of the brain and spine: leptomeningeal and cranial nerve enhancement
• Cerebrospinal fluid analysis: higher specificity but less sensitivity than MRI
  • ↑ Opening pressure
  • Cytology shows tumor cells
  • ↑ Leukocytes
  • ↑ Total protein
  • ↓ Glucose
  • ↑ Lactate

MRI and CSF analysis are complementary and therefore used together to diagnose neoplastic meningitis.
References:^[2]

Neoplastic meningitis is usually a sign of advanced disease with systemic spread, and therefore has a very poor prognosis. The exact course of treatment depends on tumor type, the extent of systemic disease, and the degree of functional impairment. Treatment typically involves a combination of the following:

• Radiation
• Intrathecal chemotherapy (e.g., methotrexate)
• Aggressive treatment of extraneural tumor
• Analgesics
• Corticosteroids
• Ventriculoperitoneal shunting: in the event of increased ICP and/or hydrocephalus secondary to obstruction from CSF drainage

References:^[2]