Best of the AANS Session-Discussant: Early Detection of Medulloblastoma Relapse by Genomic Profiling of CSF-Derived Circulating Tumor DNA

Video Transcription

Hello, this is Will Curry, Director of Neurosurgical Oncology at Mass General Hospital, and it's  my pleasure to discuss the work presented by Raul Kumar and colleagues out of St. Jude's in Memphis.  Congratulations to the group, and congratulations to Raul for winning the James T. Rutka Pediatric Brain Tumor Award.  Well deserved, and we look forward to your continued work and future contributions to the field. Welcome to neurosurgery.  Ideally, liquid biopsy for cancer can be a less invasive and potentially more accurate and useful way for diagnosis, for detection of minimal residual disease, for molecular  profiling of tumor, and for evaluation of tumor of treatment response. A number of technologies are being examined in cancer and in brain tumors, including the  detection of circulating whole tumor cells, tumor-derived exosomes, and cell-free DNA, like in this study and subjects with medulloblastoma.  Here in what appears to be a relatively straightforward technical approach, the investigators harvested  free DNA from the CSF of patients with known medulloblastoma at various time points and performed genome-wide copy number variation profiling.  Their results are probably the strongest demonstration to date of our ability to longitudinally gather  useful genetic information from CSF or blood in patients with intracranial tumors. While copy number variation may seem like a blunt instrument, it was highly concordant  between CSF-derived genetic material and that taken directly from solid medulloblastoma.  Furthermore, the detectability of copy number variance in CSF after treatment more accurately heralded disease recurrence than did MRI with or without CSF cytology.  Liquid biopsy will almost inevitably play a role in cancer diagnosis, response evaluation, and prognosis for tumors in the central nervous system.  A one-size-fits-all approach is unlikely to be useful across cancers or even across molecular subtypes of the same pathology.  This paper is a significant step towards realizing highly sensitive detection of relevant  and prognostic tumor genetic material in the CSF of patients with certain subtypes of medulloblastoma.

Video Summary

In this video, Dr. Will Curry from Mass General Hospital discusses the work presented by Raul Kumar and colleagues at St. Jude's in Memphis. Raul won the James T. Rutka Pediatric Brain Tumor Award. The study focuses on liquid biopsy as a less invasive and potentially more accurate way of diagnosing and detecting minimal residual disease in medulloblastoma patients. The researchers harvested free DNA from the CSF of patients at different time points and performed genome-wide copy number variation profiling. The results showed that copy number variation in CSF was highly concordant with solid medulloblastoma samples and was more accurate in predicting disease recurrence than MRI. This study is an important step towards detecting genetic material in the CSF of certain medulloblastoma subtypes.

Asset Caption

William T. Curry, Jr., MD, FAANS

Keywords

liquid biopsy

minimal residual disease

CSF

copy number variation

medulloblastoma subtypes