Clinical and Technical Aspects of Photodynamic Therapy – Superficial and Interstitial Illumination in Skin and Prostate Cancer

Abstract

Clinical and technical aspects of photodynamic therapy are reviewed with emphasis on the treatment of skin tumors as examples of superficial lesions with perpendicular illumination and prostate cancer as an example of deeply embedded tumors requiring interstitial intervention. The field is surveyed with a special perspective based on studies for more than 20 years on the clinical and technical aspects of research pursued in an interdisciplinary setting at the Lund University Medical Laser Center. In particular, the interplay between optical diagnostics and dosimetry and the delivery of the therapeutic light dose is highlighted. Examples of fluorescence demarcation to guide the treatment inclusion zone in non‐melanoma skin malignancies are given. A multiple fiber interstitial and interactive procedure to deliver the required therapeutic light dose based on measured light fluence, sensitizer, and oxygen concentration levels in the tumor is presented. Application to the eradication of prostate cancer is illustrated.

Clinical Practice of Photodynamic Therapy for Non-Small Cell Lung Cancer in Different Scenarios: Who Is the Better Candidate?

“…Ideal dosimetry should not only offer maximum tumor ablation but also minimize adverse effects [13]. Hyperthermia and PDT may act synergistically, while overheating (over 300 or 400 mW/cm 2 irradiation) may lead to fibrosis, bleeding, perforation, and tissue deformation [8,9,14,15]. However, it is difficult to determine the proper dosimetry because of complicated and unmeasurable factors, such as individual variability, the optical property of the tissue, etc.…”

Medical laser application: translation into the clinics

“…PDT is increasingly being used amongst health practitioners in combating a variety of diseases. 49 In the field of 5-ALA based PDT, a variety of clinical approaches are either under investigation or in clinical trials, which include the areas of dermatology, urology, brain, otorhinolaryngology, gynecology, and gastroenterology. In the following, the translation of basic scientific investigations to clinical application is sketched for the case of neurosurgery.…”

Feasibility of interstitial diffuse optical tomography using cylindrical diffusing fibers for prostate PDT

“…Interstitial photodynamic therapy (PDT) has been used as a treatment modality for prostate cancer (Weersink et al 2005, Verigos et al 2006, Windahl et al 1990, Svanberg et al 2010, Trachtenberg et al 2007, 2008, Du et al 2006, Patel et al 2008. During treatment, light sources are inserted into the prostate using a geometrical template and catheters under image guidance, usually transrectal ultrasound (TRUS), in a fashion similar to the prostate permanent implant treatment.…”