Immuno-PET for Glioma Imaging: An Update

Abstract

Despite significant advances in glioma diagnosis and treatment, overall outcomes remain suboptimal. Exploring novel therapeutic avenues show promise in advancing the field. Theranostics, an evolving discipline integrating diagnosis and therapy, emerges as a particularly auspicious approach. However, an unmet need exists for glioma-associated biomarkers as theranostic targets. Immuno-positron emission tomography (Immuno-PET), a pioneering method uniting PET diagnostic precision with antibody specificity, holds potential for identifying cancer-associated biomarkers. This review aims to provide an updated overview of immuno-PET applications in gliomas. Notably, [44Sc]-CHX-A″-DTPA-Cetuximab-Fab targeting Epidermal Growth Factor Receptor (EGFR) has displayed promise in glioma xenografts, enabling potential imaging at 4 h post-injection. Similarly, [89Zr]-bevacizumab targeting vascular endothelial growth factor (VEGF) yielded encouraging results in preclinical models and a pioneering clinical trial for pediatric patients with diffuse intrinsic pontine glioma (DIPG). Several cell differentiation markers, including CD146, indicative of tumor aggressiveness, and CD11b, reflecting tumor-associated myeloid cells (TAMCs), proved effective targets for immuno-PET. Additionally, immuno-PET directed at prostate-specific antigen (PSMA) demonstrated efficacy in imaging glioma-associated neovasculature. While holding promise for precise diagnosis and treatment guidance, challenges persist in achieving target specificity and selecting suitable radionuclides. Further studies are imperative to advance the field and bridge a translational gap from bench to bedside.

Keywords

• gliomas
• positron emission computed tomography
• precision medicine
• gallium-68
• zirconium-89
• monoclonal antibodies