Photodynamic Therapy in Oncology

Abstract

Photodynamic therapy (PDT) is increasingly being recognized as an attractive, alternative treatment modality for superficial cancer. Treatment consists of two relatively simple procedures: the administration of a photosensitive drug and illumination of the tumor to activate the drug. Efficacy is high for small superficial tumors and, except for temporary skin photosensitization, there are no long-term side effects if appropriate protocols are followed. Healing occurs with little or no scarring and the procedure can be repeated without cumulative toxicity. Considering the efficacy and lack of long-term toxicity of PDT, and the fact that the first treatment of cancer with PDT was done more than 100 years ago, one might expect that this treatment had already become an established therapy. However, PDT is currently offered in only a few selected centers, although it is slowly gaining acceptance as an alternative to conventional cancer therapies. Here, we show the developmental steps PDT underwent and summarize the current clinical applications. The data show that, when properly used, PDT is an effective alternative treatment option in oncology. The

Vascular-targeted photodynamic therapy with BF2-chelated Tetraaryl-Azadipyrromethene agents: a multi-modality molecular imaging approach to therapeutic assessment

“…The efficacy of PDT in the treatment of cancer depends on photosensitiser concentration and localisation, coupled with light dose (fluence), and oxygen availability. The singlet oxygen generated by the photochemical reaction of photosensitiser and light can directly kill tumour cells through the induction of apoptosis and/or necrosis, or may damage the tumour vasculature and healthy vessels, resulting in hypoxia and oxygen starvation, thus causing indirect tumour kill (Triesscheijn et al, 2006). In addition, PDT can initiate an immune response against the remaining tumour cells.…”

“…In addition, PDT can initiate an immune response against the remaining tumour cells. The outcome of PDT is dependent on all these mechanisms and the relative contribution of each depends on the treatment regimen employed (Triesscheijn et al, 2006).…”

Clinical Photodynamic Therapy Review and the Brazilian Experience

“…Light sources for tumor treatment range from conventional lamp bulbs either with or without optical filters [56] to light-emitting diodes (LED) [16,57,58] andlasers [21,59,60] . The latter ones are the most versatile and thus the most used ones, due to the possibility of coupling optical fibbers to provide light delivery to treatment spots difficult to reach.…”

Enhanced antitumor effects of BPD-MA-mediated photodynamic therapy combined with adriamycin on breast cancer in mice

“…Photodynamic therapy (PDT) is increasingly being recognized as an attractive alternative treatment modality for superficial cancer [3,4] , and this therapy has already been used on patients suffering from cancers of the skin or mouth. Additionally, it is presumed that this form of therapy may replace the use of radiotherapy in a number of breast cancer patients.…”