Nat Med: New developments: Blood tests can accurately identify different types of brain tumors

Recently, researchers have discovered a simple but highly sensitive blood test that accuratelydiagnoseand classify different types of brain tumors, providing patients with more accurate and intrusive treatment plansthe discovery was published in Nature Medicine on June 22, 2020, entitled "Detect and Discrimination of the intracranial tumor s cell-free DNA methylomes"The study describes a non-invasive and simple way to classify brain tumorsThe study was actually presented at the opening plenary session of the prestigious American Association for Cancer Research's 2020 annual meeting on the topic of turning science into life-saving careone of the main challenges in treating brain cancer is to accurately diagnose different types of brain cancer, from low-level tumors that appear to appear to be almost normal under a microscope to tumors of varying degrees of aggressionCancer grading is used to determine prognosis and assist in developing treatment planscurrent methods for diagnosing and determining brain cancer subtypes based on molecular information rely on invasive surgical techniques to obtain tissue specimens, a high-risk process that can also cause anxiety in patientsthe ability to diagnose and classify brain tumor types without tissue samples is revolutionary and practice is changingIn some cases, surgery may not even be required"If we have a better and more reliable way to diagnose and develop tumor subtypes, it will have a huge impact on how we treat these cancers and how we plan to treat them," said Gelareh Zadeh, medical director of the Krembil Brain Institute and director of surgical oncology at princess Margaret Cancer Center and a senior scientist and professor of surgeryDrDrZadeh and DrDaniel De Carvalho, senior scientist at princess Margaret Cancer Center Dr Daniel de Carvalho is a world leader in applying cancer epigenetics to early detection, classification and new therapeutic interventions Dr Zad Carvalho's lab specializes in an epigenetic modification called DNA methylation, which plays an important role in regulating gene expression within cells (turning on or off genes) In cancer cells, DNA methylation patterns are disrupted, causing uncontrolled cancer cells to grow Dr Zad Carvalho previously developed a DNA-based liquid biopsy method to analyze epigenetic changes in thousands of these DNA molecules in the blood These fragments are called circulating tumor DNA or ctDNA Combining this new technology with machine learning, his team was able to develop a highly sensitive and accurate detection method to detect and classify multiple solid tumors Dr Zadeh and Dr de Carvalho decided to use the same method for the challenging application of intracranial tumor classification Clinicians and scientists tracked the origin and type of cancer by comparing patients with samples of pathological tumors of brain cancer and analyzing free DNA in the plasma of 221 patients using this method, they were able to match plasma circulation ctDNA with tumor DNA to confirm that they were able to identify brain tumor DNA circulating in the blood of these patients Then, using machine learning, they developed a computer program that classifies brain tumor types based only on circulating tumor DNA Dr , , said that before that, it was not thought possible to detect any brain cancer by blood tests because the blood-brain barrier was impermeable The blood-brain barrier is between the blood vessels and tissues of the brain, protecting the brain from any toxins in the blood But because the test is so sensitive to detecting even a small number of highly specific tumor source signals in the blood, there is now a new, non-invasive way to detect and distinguish common brain tumors, which has long been considered impossible Canadian research chairman and associate professor At the University of Toronto, Dr Daniel de Carvalho, in Cancer Epigenetics, added that identifying tumor-specific changes in the field with new ctDNA, more sensitive tests in various bodies such as blood and urine are currently a turning point, because advanced technology can detect and analyze even the smallest traceofs of molecular characteristics from large numbers of circulating tumor DNA fragments ? Dr Carvalho said, "The possibility of mapping epigenetic modification across the genome, combined with powerful computational methods, has taken us to this critical point, allowing us to gain a more comprehensive understanding of the changing characteristics of tumors by analyzing epigenetic changes and genetic mutations to describe the molecular properties of tumors, and providing the possibility for more specific, sensitive and uncertain tumor testing." "
? In a paper published June 22, 2020 in the journal Nature Medicine, Dr Carvalho and his co-authors from Harvard University's Dana-Farber Cancer Institute said the same blood test scans can accurately identify kidney cancer by circulating cell free DNA extracted from plasma or urine