Photodynamic Therapy: A Compendium of Latest Reviews (original) (raw)

Photodynamic therapy of cancer: An update

CA: A Cancer Journal for Clinicians, 2011

Photodynamic therapy (PDT) is a clinically approved, minimally invasive therapeutic procedure that can exert a selective cytotoxic activity toward malignant cells. The procedure involves administration of a photosensitizing agent followed by irradiation at a wavelength corresponding to an absorbance band of the sensitizer. In the presence of oxygen, a series of events lead to direct tumor cell death, damage to the microvasculature, and induction of a local inflammatory reaction. Clinical studies revealed that PDT can be curative, particularly in early stage tumors. It can prolong survival in patients with inoperable cancers and significantly improve quality of life. Minimal normal tissue toxicity, negligible systemic effects, greatly reduced long-term morbidity, lack of intrinsic or acquired resistance mechanisms, and excellent cosmetic as well as organ function-sparing effects of this treatment make it a valuable therapeutic option for combination treatments. With a number of recent technological improvements, PDT has the potential to become integrated into the mainstream of cancer treatment. CA Cancer J Clin 2011;61:250-281

Photodynamic Therapy (PDT) in Oncology

Cancers

The issue is focused on Photodynamic Therapy (PDT), which is a minimally invasive therapeutic modality approved for treatment of several types of cancer and non-oncological disorders [...]

Photodynamic Therapy in the Treatment of Cancer: A review

Journal of Integrative Medicine

The search for non-invasive or minimally invasive approaches for the treatment of cancer has led to the development of different therapeutic regimes and one such regime is photodynamic therapy (PDT). PDT is a non-thermal treatment based on the synergy of three elements: the administration of a photosensitizer drug; light at a precise wavelength; and the presence of oxygen. When these three components are combined, they lead to the formation of reactive oxygen species (ROS), resulting in a complex cascade of events and subsequent cell death Studies revealed that PDT can prolong survival in patients with inoperable cancers and significantly improve the quality of life. With a number of recent technological improvements, PDT has the potential to become integrated into the mainstream strategy for cancer treatment. In this review, we have addressed the most important biological and physicochemical aspects of PDT, summarized its clinical status and provided an outlook for its potential fu...

Photodynamic therapy in cancer treatment -an update review

Journal of Cancer Metastasis and Treatment , 2019

Cancer remains a worldwide health problem, being the disease with the highest impact on global health. Even with all the recent technological improvements, recurrence and metastasis still are the main cause of death. Since photodynamic therapy (PDT) does not compromise other treatment options and presents reduced long-term morbidity when compared with chemotherapy or radiotherapy, it appears as a promising alternative treatment for controlling malignant diseases. In this review, we set out to perform a broad update on PDT in cancer research and treatment, discussing how this approach has been applied and what it could add to breast cancer therapy. We covered topics going from the photochemical mechanisms involved, the different cell death mechanisms being triggered by a myriad of photosensitizers up to the more recent-ongoing clinical trials.

Photodynamic therapy--indications and limits in malignant tumors treatment

Romanian journal of internal medicine = Revue roumaine de médecine interne, 2008

Photodynamic therapy (PDT) is a very promising technique used for the treatment of a variety of solid neoplasms, based on the formation of singlet oxygen induced by a photosensitizer after irradiation with visible light. The mechanism of interaction of the photosensitizers and light is discussed, along with the effects produced in the target tissue. PDT has been approved in many countries for the treatment of lung, esophageal, bladder, skin and head and neck cancers. The antitumor effects of this treatment result from the combination of direct tumor cell photodamage, destruction of tumor vasculature and activation of an immune response. The present status of clinical PDT is discussed along with the newer photosensitizers being used and their clinical roles. Despite the promising results from earlier clinical trials of PDT considerable additional work is needed to bring this new modality of treatment into modern clinical practice.

Photodynamic Therapy and Its Role in Combined Modality Anticancer Treatment

Technology in cancer research & treatment, 2014

Photodynamic therapy (PDT) is a relatively new modality for anticancer treatment and although the interest has increased greatly in the recent years, it is still far from clinical routine. As PDT consists of administering a nontoxic photosensitizing chemical and subsequently illuminating the tumor with visible light, the treatment is not subject to dose-limiting toxicity, which is the case for established anticancer treatments like radiation therapy or chemotherapy. This makes PDT an attractive adjuvant therapy in a combined modality treatment regimen, as PDT provides an antitumor immune response through its ability to elicit the release of damage-associated molecular patterns and tumor antigens, thus providing an increased antitumor efficacy, potentially without increasing the risk of treatment-related toxicity. There is great interest in the elicited immune response after PDT and the potential of combining PDT with other forms of treatment to provide potent antitumor vaccines. Thi...

Strategies for Enhanced Photodynamic Therapy Effects

Photochemistry and Photobiology, 2007

Photodynamic therapy (PDT) is a treatment modality for the selective destruction of cancerous and nonneoplastic pathologies that involves the simultaneous presence of light, oxygen and a light-activatable chemical called a photosensitizer (PS) to achieve a cytotoxic effect. The photophysics and mechanisms of cell killing by PDT have been extensively studied in recent years, and PDT has received regulatory approval for the treatment of a number of diseases worldwide. As the application of this treatment modality expands with regard to both anatomical sites and disease stages, it will be important to develop strategies for enhancing PDT outcomes. This article focuses on two broad approaches for PDT enhancement:

Photodynamic therapy of cancer. Basic principles and applications

Clinical & Translational Oncology, 2008

Photodynamic therapy (PDT) is a minimally invasive therapeutic modality approved for clinical treatment of several types of cancer and non-oncological disorders. In PDT, a compound with photosensitising properties (photosensitiser, PS) is selectively accumulated in malignant tissues. The subsequent activation of the PS by visible light, preferentially in the red region of the visible spectrum (λ≥600 nm), where tissues are more permeable to light, generates reactive oxygen species, mainly singlet oxygen (1O2), responsible for cytotoxicity of neoplastic cells and tumour regression. There are three main mechanisms described by which 1O2 contributes to the destruction of tumours by PDT: direct cellular damage, vascular shutdown and activation of immune response against tumour cells. The advantages of PDT over other conventional cancer treatments are its low systemic toxicity and its ability to selectively destroy tumours accessible to light. Therefore, PDT is being used for the treatment of endoscopically accessible tumours such as lung, bladder, gastrointestinal and gynaecological neoplasms, and also in dermatology for the treatment of non-melanoma skin cancers (basal cell carcinoma) and precancerous diseases (actinic keratosis). Photofrin®, ALA and its ester derivatives are the main compounds used in clinical trials, though newer and more efficient PSs are being evaluated nowadays.

Approaches to improve photodynamic therapy of cancer

2011

Introduction 3. Major advantages and disadvantages of PDT-what needs improvement or might be improved? 4. New photosensitizers 5. New light sources 6. Targeting cytoprotective mechanisms in PDT-treated cells 6.1. ROS-scavenging enzymes 6.2. Handling of damaged proteins 6.3. Mechanisms not directly associated with ROS scavenging 7. Combinations of PDT with other treatment modalities 8. Enhancement of PDT-mediated immune response 8.1. Immunoadjuvants 8.2. Cytokines 8.3. Adoptive immunotherapy 8.4. Introduction of foreign antigens 8.5. Anticancer therapeutics 9. Other new directions 9.1. Photochemical internalization 9.2. Metronomic PDT 9.3. Nanoparticle-based PDT 9.4. Two photon PDT 10. Conclusions 11. Acknowledgments 12. References Photodynamic therapy of cancer nanovehicle preparation for photodynamic therapy in vitro.