Ultrasound mediated blood-brain barrier opening increases brain tumor biomarkers: A review of preclinical and clinical trials

Abstract

The diagnosis of brain tumors typically relies on magnetic resonance imaging (MRI), computed tomography (CT), and invasive procedures like biopsies or surgical resection for confirmation and genetic profiling. However, these methods have limitations, especially in distinguishing treatment effects like pseudo-progression from actual tumor progression, and repeated biopsies pose risks. Liquid biopsy (LB) offers a non-invasive alternative, detecting tumor-derived biomarkers in blood and cerebrospinal fluid (CSF). Despite its potential, the low concentration of brain tumor biomarkers in blood due to the blood-brain barrier (BBB), limits the clinical utility of LB. MRI-guided focused ultrasound (MRgFUS) combined with microbubbles provides a novel solution by temporarily disrupting the BBB, facilitating the passage of therapeutic agents, and enabling tumor biomarker detection. This technique, termed “sonobiopsy,” enables non-invasive biomarker collection for liquid biopsy, potentially improving brain tumor diagnosis and monitoring.