For patients with suspected Leptomeningeal Metastases, time matters – prompt diagnosis and treatment initiation are essential to improve the chances of controlling the disease, managing symptoms, and extending survival.

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CNSide® (Pronounced: see-inside)

CNSide®, a proprietary, highly sensitive, cerebrospinal fluid (CSF) assay platform performed in a CLIA accredited laboratory, provides healthcare professionals with accurate, comprehensive data that enable detection, quantitative analysis, and molecular characterization of tumor cells.1 The resulting data are indispensable in diagnosing LM, identifying biomarkers, and monitoring the effects of treatment.2

Leptomeningeal Metastases (LM)

Get information about this devastating complication of advanced cancer.

CNSide® Cerebrospinal Fluid Assay Platform

Expect more from CSF analysis to detect and monitor solid tumors.

Our Company, Lab, and Dedicated Team

Learn about our core purpose today and aspirations for the future.

What Physician Experts Say

CNSide® is a more sensitive and definitive test for LM and has the potential to permit earlier diagnosis, manage our patients with more diagnostic precision, and hopefully improve therapeutic outcomes for our patients with LM.

Priya Kumthekar, MD

Professor of Neurology and Medicine, Northwestern University

I just want to share that this is amazing!

This drop in [my patient’s] CSF CTCs also correlates with her clinical status after treatment, and she is so happy to see the numbers drop so much. This is exactly why we need this assay: to be able to quantify the patient’s disease so we know if they are responding to treatments or not. As you know, CSF cytology is a simple yes vs. no and therefore not very helpful, as it doesn’t tell us if the disease is responding to treatment or not, not to mention the sensitivity of CSF cytology is so low that it doesn’t always give us an accurate answer.

Jonathan Yang, MD, PhD

Radiation Oncologist, NYU Langone

Health Insurance Coverage & Access

Some of the largest health insurance providers in the United States cover the CNSide® Cerebrospinal Fluid (CSF) Tumor Cell Enumeration test for metastatic central nervous system cancer, including:

  • United Healthcare
  • Humana
  • Highmark
  • Blue Shield of California

Read the full press releases

CNSide Diagnostics now available in all 50 states

81 million covered lives

Expect more from your CSF tumor cell analysis.

Your cancer patients’ lives are counting on it.

References: 1. 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. 2. 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.