A systematic review of photodynamic therapy in the treatment of pre-cancerous skin conditions, Barrett's oesophagus and cancers of the biliary tract, brain, head and neck, lung, oesophagus and skin

Photodynamic therapy (PDT) is the use of a light-sensitive drug, in combination with light of a visible wavelength, to destroy target cells. PDT is used either as a primary treatment or as an adjunctive treatment. It is fairly well accepted in clinical practice for some types of skin cancer but has yet to be fully explored as a treatment for other forms of cancer. To systematically review the clinical effectiveness and safety of PDT in the treatment of Barrett's oesophagus, pre-cancerous skin conditions and the following cancers: biliary tract, brain, head and neck, lung, oesophageal and skin. The search strategy included searching electronic databases (between August and October 2008), followed by update searches in May 2009, along with relevant bibliographies, existing reviews, conference abstracts and contact with experts in the field. Randomised controlled trials (RCTs) in skin conditions and Barrett's oesophagus, non-randomised trials for all other sites. People with Barrett's oesophagus, pre-cancerous skin conditions or primary cancer in the following sites: biliary tract, brain, head and neck, lung, oesophageal and skin. Any type of PDT for either curative or palliative treatment. Any comparator including differing applications of PDT treatments (relevant comparators varied according to the condition). The outcomes measured were mortality, morbidity, quality of life, adverse events and resource use. A standardised data extraction form was used. The quality of RCTs and non-randomised controlled studies was assessed using standard checklists. Data extracted from the studies were tabulated and discussed in a narrative synthesis, and the influence of study quality on results was discussed. Meta-analysis was used to estimate a summary measure of effect on relevant outcomes, with assessment of both clinical and statistical heterogeneity. Two reviewers independently screened all titles and abstracts, and data extracted and quality assessed the trials, with discrepancies resolved by discussion or referral to a third reviewer. A scoping review was also undertaken. Overall, 88 trials reported in 141 publications were included, with some trials covering more than one condition. For actinic keratosis (AK), the only clear evidence of effectiveness was that PDT appeared to be superior to placebo. For Bowen's disease, better outcomes with PDT were suggested when compared with cryotherapy or fluorouracil. For basal cell carcinoma (BCC), PDT may result in similar le