NCT07476781

CSF and Blood Plasma Liquid Biopsy in Patients With Metastatic Solid Tumours and CNS Metastases or no CNS Metastases

Exploring the Feasibility of Cerebrospinal Fluid (CSF) Liquid Biopsy in Patients With Metastatic Solid Tumours and Leptomeningeal Disease (Cohort A), Parenchymal Brain Metastases (Cohort B), or No Evidence of Central Nervous System (CNS) Metastases (Cohort C): A Pilot Study

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 60 (estimated)
• Sponsor: Sunnybrook Health Sciences Centre · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This is a prospective, single-centre feasibility study of CSF ctDNA conducted at the Sunnybrook Odette Cancer Centre (SOCC), Toronto, Canada, including multiple solid tumor, stratified into cohorts according to CNS disease involvement, including leptomeningeal disease (Cohort A), parenchymal brain metastases (Cohort B), and no evidence of CNS metastases (Cohort C).

Detailed description

Current plasma-based liquid biopsy approaches have limited ability to reflect CNS disease in patients with solid tumor. Since CSF is in direct contact with CNS disease, CSF analysis may provide more relevant biological information; however, its role as a liquid biopsy source has not been well characterized across different patterns of CNS involvement. The goal of this pilot study is to evaluate the feasibility and utility of CSF-based liquid biopsy in patients with solid tumor with and without CNS metastases. Three predefined cohorts will be studied: patients with leptomeningeal disease (Cohort A), patients with active parenchymal brain metastases (Cohort B), and patients without evidence of parenchymal brain metastases (Cohort C). Participants will undergo a one-time CSF collection via lumbar puncture or Ommaya reservoir, with concurrent collection of peripheral blood for plasma-based liquid biopsy. Aim 1: To determine the proportion of patients with positive CSF biomarkers, including cytology, circulating tumor DNA (ctDNA), and circulating tumor cells (CTCs), in each cohort. Aim 2: To compare ctDNA and CTC results obtained from CSF with those obtained from plasma in each cohort. Aim 3: To evaluate the feasibility of performing proteomic analysis using CSF samples in patients with at least one positive CSF biomarker (cytology and/or ctDNA and/or CTCs). If successful, the investigators will explore proteomic analyses in CSF biomarker negative patients to potentially identify more sensitive signatures for CNS metastasis detection.

Conditions

• Solid Tumor Malignancies
• Brain Metastasases
• Leptomeningeal Disease (LMD)

Interventions

Type	Name	Description
PROCEDURE	One time CSF and blood sample	One-time CSF collective via lumbar puncture or Ommaya reservoir and collection of concurrent plasma of peripheral blood (liquid biopsy).

Timeline

• Start date: 2025-12-12
• Primary completion: 2026-12-01
• Completion: 2026-12-01
• First posted: 2026-03-17
• Last updated: 2026-03-17

Locations

1 site across 1 country: Canada