Figure 1.

a. Patients with glioblastoma, post-surgical resection and chemoradiation, are monitored using serial MR imaging. A gadolinium enhancing lesion on contrast enhanced magnetic resonance imaging (MRI) could either be true progressive disease (PD), or radiation effects such as pseudoprogression or radiation necrosis (RN). Liquid biopsy strategies including circulating tumor cells (CTCs), circulating free DNA (CfDNA), extracellular vesicles (EVs) can provide minimally invasive modalities of monitoring brain tumors. b. Three-pronged monitoring approach using integrating clinical status, imaging modalities and liquid biopsy strategies could be a potential solution for tracking the tumor evolution over time and therapy. Blood vessel image from Smart Servier.