A novel, multianalyte test has been developed to identify central nervous system cancers from small samples of cerebrospinal fluid (CSF). In findings published in Cancer Discovery, the study authors reported that the test, called CSF-BAM, achieved a sensitivity of 81% and a specificity of 100%.
The findings highlight that a more effective test for identifying central nervous system cancers requires use of more than one biological marker. “This study highlights how much more information we can gain when we evaluate several analytes together,” stated senior study author Chetan Bettegowda, MD, PhD, Harvey Cushing Professor and Director of the Department of Neurosurgery at the Johns Hopkins University School of Medicine, Director of the Reza Khatib Brain Tumor Research Center at Johns Hopkins, and Medical Director of the Ludwig Center. “The ability to detect cancers with high specificity and also gain insight into the immune environment of the brain could be an important advance in the care of patients with brain tumors.”
Study Methods and Rationale
Current methods for identifying brain tumors are invasive and potentially dangerous. Less invasive methods are needed for detection and diagnosis.
The study authors combined multiple biological markers into one multianalyte test for looking at B-cell and T-cell receptor sequences, aneuploidy, and tumor-specific genetic mutations for the detection of central nervous system tumors in the amplification of both DNA strands of cerebrospinal fluid. They tested CSF-BAM on 206 cerebrospinal fluid samples from patients with high-grade gliomas, medulloblastomas, brain metastases, and central nervous system lymphomas in a validation cohort, followed by 129 cerebrospinal fluid samples from patients with the most common aggressive cancer types.
Key Study Findings
In the validation cohort, the CSF-BAM test identified brain cancers with an 81% sensitivity plus a 100% specificity for identifying samples without cancer. The test was also able to distinguish between immune cell populations for cancerous and noncancerous cases, which may be helpful for diagnosing more challenging cases, including in situations where biopsy is too dangerous or imaging or cytology is inconclusive.
“Many patients with brain lesions face invasive diagnostic procedures to confirm a cancer diagnosis,” said Christopher Douville, MD, Assistant Professor of Oncology at Johns Hopkins University School of Medicine and a senior study author. “A tool like this could help us make better-informed decisions about who really needs a biopsy and who doesn’t.”
Disclosure: The research was funded by grants from the National Cancer Institute, Alex's Lemonade Stand Foundation, American Society of Hematology Scholar Award, etc. For full disclosures of the study authors, visit aacrjournals.org.
