Zaak, Dirk; Sroka, Ronald; Stocker, Susanne; Bise, Karl; Lein, Michael; Höppner, Michael; Frimberger, Dominic; Schneede, Peter; Reich, Oliver; Kriegmair, Martin; Knüchel, Ruth; Baumgartner, Reinhold; Hofstetter, Alfons (2004): Photodynamic therapy of prostate cancer by means of 5-aminolevulinic acid-induced protoporphyrin IX - In vivo experiments on the dunning rat tumor model. In: Urologia Internationalis, Nr. 3: S. 196-202




Objective: In order to expand the use of photodynamic therapy (PDT) in the treatment of prostate carcinoma (PCA), the aim of this study was to evaluate PDT by means of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX ( PPIX) in an in vivo tumor model. Methods: The model used was the Dunning R3327 tumor. First of all, the pharmacokinetics and the localization of PPIX were obtained using fluorescence measurement techniques. Thereafter, PDT using 150 mg 5-ALA/kg b.w.i.v. was performed by homogenous irradiation of the photosensitized tumor (diode laser lambda = 633 nm). The tumors necrosis was determined histopathologically. Results: The kinetics of PPIX fluorescence revealed a maximum intensity in the tumor tissue within 3 and 4.5 h post-application of 5-ALA. At this time, specific PPIX fluorescence could be localized selectively in the tumor cells. The PDT-induced necrosis (n = 18) was determined to be 94 B 12% (range 60-100%), while the necrosis of the controls ( n = 12) differs significantly (p < 0.01), being less than 10%. Conclusion: These first in vivo results demonstrate the effective potential of 5-ALA-mediated PDT on PCA in an animal model. Copyright (C) 2004 S. Karger AG, Basel.