Photodynamic therapy for cancer of the pancreas – The story so far

Abstract

Pancreatic cancer has long been a leading cause of cancer death. Few patients are suitable for surgery and for those who are not, the response to treatment is generally poor. No more than about 10% survive for more than a year. Recent research has focused on focal treatment for local disease control. This review covers the development of one of the most promising options, photodynamic therapy (PDT).This review covers pre-clinical and clinical studies. Laboratory work was designed to understand the effect of PDT on the normal pancreas and surrounding tissues and on transplanted cancers in the hamster pancreas to ensure safety prior to clinical application. Essentially all clinical studies have been undertaken in University College Hospital, London. Phase-I studies used the photosensitisers mTHPC and verteporfin in patients with localised but inoperable cancers.Laboratory results showed that normal pancreas, bile duct, liver, stomach and major blood vessels could tolerate PDT without any unacceptable effects on the structure and function of these organs. Necrosis that healed safely was documented in transplanted cancers. The clinical trials showed that focal necrosis could be produced in inoperable cancers with acceptable levels of complications, but considerable refinements of treatment delivery and monitoring are required before the technique will be ready for assessment in controlled clinical trials.PDT is showing promise for the minimally invasive treatment of localised pancreatic cancers, but it is still at an early stage of development. Much more work will be necessary to optimise techniques for applying PDT to these cancers and for combining it with other therapeutic options such as chemotherapy.

Photodynamic Therapy: A Compendium of Latest Reviews

“…Furthermore, they highlighted that the combination of various treatments (including targeted, immunotherapy, or cannabidiol) might be a justified strategy for colorectal cancer treatment. PDT has proved a possible option for minimally invasive treatment for the pancreas, but it is still at an early stage of development [36]. In Ref.…”

Anticancer platinum agents and light

“…Results obtained in PC-3 cells, demonstrated that the catalyst-substrate pair Rf/39 was not toxic in the dark, while upon blue light irradiation cell viability was reduced to values comparable to cisplatin. On the other hand, Capan-1 cells were tested because they showed high tolerance against singlet oxygen damaging [86][87][88]. Viability experiments in this cell line suggested that the pair (Rf/39) was also effective under regimes in which PDT was not effective, because of the selective photocatalytic activation of the Pt IV substrate [89].…”

Considerations and Technical Pitfalls in the Employment of the MTT Assay to Evaluate Photosensitizers for Photodynamic Therapy

“…Photodynamic therapy (PDT) is employed to treat a variety of skin diseases (such as actinic keratosis, basal cell carcinoma, and psoriatic plaque) [1][2][3][4] cancers (of the lung, bladder, colon, prostate, gastrointestinal, pancreatic, and breast), and fungal infections [5][6][7][8][9][10][11]. In PDT, exposure to light of the appropriate wavelength (400-700 nm) alters the conformation of a photosensitizer molecule, generating radicals and/or reactive oxygen species (ROS) that destroy the target cells [12][13][14][15].…”