Source:Optical Methods and Instrumentation in Brain Imaging and Therapy, Springer New York, Number Bioanalysis Volume 3, New York, NY, p.253 - 271 (2013)
The diffuse and infiltrative nature of high grade gliomas, such as glioblastoma multiforme (GBM), makes complete surgical resection virtually impossible. The propensity of glioma cells to migrate along white matter tracts suggests that a cure is possible only if these migratory cells can be eradicated. Approximately 80% of GBMs recur within 2 cm of the resection margin, suggesting that a reasonable approach for improving the prognosis of GBM patients would be the development of improved local therapies capable of eradicating glioma cells in the brain-adjacent-to-tumor (BAT). An additional complicating factor for the development of successful therapies is the presence of the blood–brain barrier (BBB) which is highly variable throughout the BAT—it is intact in some regions, while leaky in others. This variance in BBB patency has significant implications for the delivery of therapeutic agents. The results of a number of studies have shown that experimental light-based therapeutic modalities such as photochemical internalization (PCI) and photothermal therapy (PTT) may be useful in the treatment of gliomas. This chapter summarizes recent findings illustrating the potential of: (1) PCI for the delivery of therapeutic macromolecules such as chemotherapeutic agents and tumor suppressor genes, and (2) nanoshell-mediated PTT, including nanoparticle delivery approaches via macrophages.