SELECTIVE TUMOR KILL OF CEREBRAL GLIOMA BY PHOTODYNAMIC THERAPY USINGA BORONATED PORPHYRIN PHOTOSENSITIZER

The prognosis for patients with the high-grade cerebral glioma gliobla stoma multiforme is poor. The median survival for primary tumors is <1 2 months, with most recurring at the site of the original tumor, indic ating that a more aggressive local therapy is required to eradicate th e unresectable ''nests'' of tumor cells invading into adjacent brain, Two adjuvant therapies with the potential to destroy these cells are p orphyrin-sensitized photodynamic therapy (PDT) and boron-sensitized bo ron neutron capture therapy (BNCT), The ability of a boronated porphyr in, 2,4-((alpha,beta-dihydroxyethyl) deuteroporphyrin Iii tetrakiscarb orane carboxylate ester (BOPP), to act as a photosensitizing agent was investigated in vitro with the C6 rat glioma cell line and in vivo wi th C6 cells grown as an intracerebral tumor after implantation into Wi star rats. These studies determined the doses of BOPP and light requir ed to achieve maximal cell kill in vitro and selective tumor kill in v ice, The data show that BOPP is more dose effective in vivo by a facto r of 10 than the current clinically used photosensitizer hematoporphyr in derivative and suggest that BOPP may have potential as a dual PDT/B NCT sensitizer.