PHARMACOKINETIC STUDIES ON 5-AMINOLEVULINIC ACID-INDUCED PROTOPORPHYRIN-IX ACCUMULATION IN TUMORS AND NORMAL-TISSUES

Laser-induced fluorescence (LIF) for in vivo point monitoring and fluo rescence microscopy incorporating a CCD camera were used to study the fluorescence distribution of 5-aminolevulinic acid (ALA)-induced proto porphyrin IX (PpIX) in tumours. Fluorescence in a chemically induced a denocarcinoma in the liver of rats and in an aggressive basal cell car cinoma in a patient were studied after intravenous injection of ALA at a dose of 30 mg/kg body weight. The LIF technique demonstrated slight ly more ALA-induced PpIX fluorescence in the tumour than in the surrou nding normal liver and abdominal muscle of rats. The visible parts of the human basal cell carcinoma exhibited strong ALA-induced fluorescen ce, while this fluorescence was much weaker in the necrotic areas of t he tumour and in the surrounding normal skin. (C) 1997 Elsevier Scienc e ireland Ltd.