Whole Bladder Photodynamic Therapy for Orthotopic Superficial Bladder Cancer in Rats: A Study of Intravenous and Intravesical Administration of Photosensitizers

ABSTRACTPurpose: Photodynamic therapy after intravenous injection of Photofrin (QLT Phototherapeutics, Vancouver, British Columbia, Canada) results in a contracted bladder and skin photosensitivity, which limits its clinical application. In an attempt to overcome these limitations photodynamic therapy after intravesical instillation of Photofrin or 5-aminolevulinic acid (ALA) in an orthotopic rat bladder tumor model was explored and compared with intravenous Photofrin for photodynamic therapy efficacy and phototoxicity.Materials and Methods: At 2 weeks after bladder implantation of 1.5 × 106 AY-27 tumor cells animals were randomly grouped. Photofrin was administered (5 mg./kg. intravenously and 2 mg./ml. intravesically). The ALA concentration for intravesical instillation was 300 mM. Whole bladder photodynamic therapy with graded doses of light (λ = 630 nm.) was performed 4 hours after drug administration. Tumor control and complications were evaluated.Results: Photodynamic therapy with intravenous Photof...