CNSide® CSF Assay is Now Covered by UnitedHealthcare

CNSide Diagnostics logo

Maintain Vigilance. 

Leptomeningeal Metastases may be lurking in your patients with solid tumors

Hear from a LM Patient

Leptomeningeal Metastases (LM)

Also called leptomeningeal carcinoma, leptomeningeal carcinomatosis, carcinomatous meningitis, neoplastic meningitis, LM is a rare and aggressive complication in which cancer cells from a primary tumor spread to the cerebrospinal fluid surrounding the brain and spinal cord.1
A microscope is used to examine a specimen.

Traditional methods for identifying LM may delay diagnosis.

Discover Why
A healthcare provider greets a patient.

Are you a patient or caregiver looking for more on LM?

Find Resources

As cancer patients live longer, the incidence of Leptomeningeal Metastases has increased²

LM is known to occur in approximately 5% of patients with solid tumors.3,4 However, the true incidence of all LM is likely higher than what current studies suggest, given the low sensitivity of traditional cytology and the insidious and asymptomatic nature of leptomeningeal seeding.1,5

Raise Your Suspicion

An early and high index of suspicion is needed to detect LM¹

Know the Signs

Radiologic abnormalities7

Cytology positive for tumor7

Know the Symptoms

General: Seizure, headaches, back pain, peritumoral edema, increased cranial pressure2,6,8

Focal: Limb weakness, hearing loss2,6,8

Neurologic: Confusion or psychiatric disorders, diplopia (double vision), cranial nerve deficits, imbalance, numb chin syndrome (NCS), or mental nerve neuropathy2,6,8,9

~0%

Occurs in ~5% of patients with solid tumors; approximately ~20% of solid tumor patients have asymptomatic or undiagnosed LM at autopsy3,4

0%-0%

Solid cancers of the lung and breast, and melanoma account for 67% to 80% of LM, they warrant closer clinical surveillance2,8

Standard of care diagnostic tools are limited when it comes to LM

MRI

Radiologic imaging is often equivocal since it is not sensitive to early involvement or treatment changes and is nonspecific (pseudo-progression)10

Cerebrospinal Fluid Cytology

Although considered the gold standard, the limitations of traditional cytology impede diagnosis

  • Tumor cells are detected in only 50% to 67% of lumbar punctures with cytology and detection is highly examiner dependent10
  • Multiple lumbar punctures may be needed to reduce false-negative results.10

Newer Methodologies

Although newer adjunctive approaches with improved sensitivity versus cytology are available, they present different limitations concerning:

  • Restriction to epithelia malignancies8
  • Inability to provide total tumor cell count11

Treatment Options

Common approaches to treatment include:

Whole brain radiation therapy or stereostatic radio surgery to help control tumor growth and symptoms.

Targeted therapies and immunotherapies that control systemic cancer and would indirectly affect LM.

Symptom management, which focuses on controlling things like pain, nausea and neurological deficits the patient may experience with LM.

Clinical trials which offer experimental treatments not widely available.

Explore Clinical Trials

Patient Advocacy and Resources

Patients and caregivers living with LM may feel alone in their disease journey, but there is a growing community of healthcare providers and advocates committed to providing resources, information and support for those living with LM.

 

Time matters.

 

Patients with LM need a more accurate and complete assessment than traditional methods offer.

It’s time for more specific, sensitive, and data-rich methods

As many as 53% of metastatic tumors contain genetic alterations with an actionable driver not detected in the primary tumor. Empower your LM management decisions with actionable data through CNSide® CSF Assay Platform.

Learn More

References: 1. Wilcox, JA, Li Jun M, Boire AA. Leptomeningeal metastases: new opportunities in the modern era. Neurotherapeutics. 2022;19(6):1782-1798. 2. Suh JH, Kotecha R, Chao ST, Ahluwalia MS, et al. Current approaches to the management of brain metastases. Nat Rev Clin Oncol. 2020;17:279-299. 3. Sharma A, Low JT, Kumthekar P. Advances in the diagnosis and treatment of leptomeningeal disease. Curr Neurol Neurosci Rep. 2022;22(7):413-425. 4. Rinehardt H, Kassem M, Morgan E, Palettas M, et al. Assessment of leptomeningeal carcinomatosis diagnosis, management and outcomes in patients with solid tumors over a decade of experience. Eur J Breast Health. 2021;17(4):371-377. 5. Barbour AB, Blouw B, Taylor LP, Graber JJ, et al. Prognostic value of cerebrospinal fluid tumor cell count in leptomeningeal disease from solid tumors. J Neurooncol. 2024;167:509–514. 6. Puri S, Malani R, Chalmers A, Kerrigan K, et al. Keeping a track on leptomeningeal disease in non–small cell lung cancer: a single-institution experience with CNSide®. Neurooncol Adv. 2024;6(1):vdad150. 7. National Comprehensive Cancer Network. Central nervous system cancers. (v 1.2025). NCCN.org. Accessed June 12, 2024. https://www.nccn.org/guidelines/guidelines-detail?category=1&id=1425. 8. Sweed NT, Hsiao H-C, Blouw B, Pircher TJ, et al. A microfluidic, multi-antibody cell capture method to evaluate tumor cells in cerebrospinal fluid in patients with suspected leptomeningeal metastases. Arch Pathol Lab Med. 2025;149(3):242-252. 9. Riesgo VJ, Delgado SR, Poveda J, Rammohan K. Numb chin syndrome secondary to leptomeningeal carcinomatosis from gastric adenocarcinoma. J Gastrointest Oncol. 2015;6(2):E16-E20. 10. Appel HR, Rubens M, Roy M, Kotecha R, et al. Comparative evaluation of the diagnostic and prognostic performance of CNSide® versus standard cytology for leptomeningeal disease. Neurooncol Adv. 2024;6(1):vdae071. 11. Kumthekar PU, Blouw B, Corkos P, Nagpal S, et al. The HER2 flip-HER2 amplification of tumor cells in the cerebrospinal fluid of breast cancer patients with leptomeningeal disease: implications for treating the LM tumor with anti-HER2 therapy. Front Oncol. 2024;14:1402651.