Liquid biopsy of gliomas with detection of extracellular tumor nucleic acids

Gliomas are the reason of fatal outcomes in an overwhelming number of patients with oncology diseases located in the central nervous system. The diagnostics of such neoplasms requires using stereotaxic biopsy, which cannot be performed in a certain percentage of the patients. Besides, this disease is characterized by high recurrence rates, despite the advances in developing resection and chemotherapy — based technologies. The early detection of oncological diseases located in the central nervous system and the differential diagnostics of tumor pseudo progression, not affecting the survival of the patient, represents a challenge for modern Medicine. Liquid biopsy is a minimally invasive diagnostic method based on the analysis of tumor derivatives (such as extracellular tumor DNA and RNA), contained within the biological fluids of the organism. For the purpose of defining the presence of the tumor component, the tests are used to detect the so-called hot-spot mutations and the patterns of epigenetic regulation, found in specific types of tumors. The technology can be used for detecting tumor recurrences and for the differential diagnostics of space-occupying mass lesions in patients, in which stereotaxic biopsy is contraindicated. The review contains a discussion on modern advances of fluid biopsy based on the analysis of the extracellular tumor DNA and RNA levels in blood plasma and in the cerebrospinal fluid of glioma patients.