[Progression of basic research, clinical application of photodynamic therapy and fluorescence-guided surgery in glioma treatment].

The prognosis of glioma remains poor because of the infiltrative nature and the high local relapse rate. The current goals for patients with gliomas is maximal safe resection and adjuvant therapy. Tumor-specific photosensitizer, such as hematoporphyrin derivative (HpD) 5-aminolevulinic acid (5-ALA), can be selective up-taken and accumulated in tumor tissue. Light with appropriate wavelength can penetrate tumor tissue and excite the photosensitizer. The excited photosensitizer within glioma cells permits fluorescence visualization of tumor tissue during surgery and has been introduced in treatment of glioma as fluorescence-guided surgery (FGS). On the other hand, the toxicity of singlet oxygen generated by the excited photosensitizer has been used as photodynamic therapy (PDT) in selective destruction of the tumor. Some reports demonstrated the usefulness of adding PDT as an intraoperative adjuvant therapy, but the complexity associated with its implementation and the introduction of TMZ prevented PDT from becoming a routine therapy. However, FGS using 5-ALA in patients with malignant brain tumors has surfaced globally and may become a useful tool in increasing the extent of resection in gliomas.