Abstract:
Polyhematoporphyrin (Photosan) as sensitizers for photodynamic therapy (PDT) in advanced esophageal cancer carry the risk of prolonged photosensitivity of the skin. New sensitizers such as 5-aminolaevulinic acid (ALA) with low rates of skin phototoxicity appear to be promising alternatives. The aim of this study was to evaluate the efficacy of ALA compared to Photosan for PDT in advanced esophageal carcinoma regarding phototoxicity of the skin, reduction of dysphagia, tumor stenosis, and tumor length and Karnovsky performance status. After diagnostic work-up, photosensitization was done in 22 patients with ALA (60 mg/kg body weight, oral, 6-8 hours prior to PDT) and in 27 patients with Photosan (2 mg/kg body weight, i.v., 48 hours before PDT). The light dose was calculated as 300 J/cm fibre tip. Light at 630 nm was applied using a pumped dye laser. In both groups, additional hyperbaric oxygenation was applied at a level of 2 absolute atmospheric pressure. Improvement regarding dysphagia, stenosis diameter, and tumor length could be obtained in both treatment arms with a significant difference in favour of the Photosan-group, P = 0.02; P = 0.0000; and P = 0.000014, respectively. The Karnovsky performance status also improved in both groups and showed no significant difference (P = 0.12). The median survival time for the ALA-group was 8.0 months, compared with 9.0 months for the Photosan group. No sunburn or other major treatment related complication occurred in both treatment arms. Thirty-day mortality was 0%. Despite the limitations of a non-randomized study, photosensitzation with Photosan seems to be more effective in PDT of advanced esophageal carcinoma compared to ALA.
Maier, Tomaselli, Matzi, Rehak, Pinter, Smolle-Jüttner, , , (2001). Does new photosensitizer improve photodynamic therapy in advanced esophageal carcinoma? Lasers in surgery and medicine, 2001 ;29(4):323-7. https://www.ncbi.nlm.nih.gov/pubmed/11746109