Towards image-guided photodynamic therapy of Glioblastoma

Abstract

Glioblastoma (GBM) is an aggressive cancer with dismal survival rates and few new treatment options. Fluorescence guided resection of GBM followed by photodynamic therapy (PDT) has shown promise in several chemo-or radiotherapy non-responsive GBM treatments clinically. PDT is an emerging light and photosensitizer (PS) mediated cytotoxic method. However, as with other therapeutic modalities, the outcomes are variable largely due to the nonpersonalization of dose parameters. The variability can be attributed to the differences in heterogeneous photosensitizer accumulation in tumors. Building upon our previous findings on utilizing PS fluorescence for designing tumor-specific PDT dose, we explore the use of photoacoustic imaging, a technique that provides contrast based on the tissue optical absorption properties, to obtain 3D information on the tumoral photosensitizer accumulation. The findings of this study will form the basis for customized photodynamic therapy for glioblastoma and have the potential to serve as a platform for treatment of other cancers.

Optical Imaging, Photodynamic Therapy and Optically Triggered Combination Treatments

“…89 Recently we demonstrated that PAI can map the heterogeneous accumulation of methylene blue (optical absorption peak around 670 nm) loaded liposomes in brain tumors to aid in personalized PDT dosimetry. 90 As active PDT agents, a concern is that PS could be photobleached during imaging procedures. To enhance PS contrast by several fold and to reduce the photobleaching effects, nanoagents comprising of imaging agents such as plasmonic gold nanoparticles in addition to PS are utilized.…”