EXPERIMENTAL PANCREATIC-CANCER IN THE RAT TREATED BY PHOTODYNAMIC THERAPY

Selective histological necrosis of experimental pancreatic carcinoma b y photodynamic therapy (PDT) has been successful with haematoporphyrin derivatives and phthalocyanine as photosensitizers. This report descr ibes the feasibility of PDT with pheophorbide A as the photo-sensitize r to treat azaserine-induced pancreatic rat carcinoma and analyses sur vival of the animals. An organ distribution study 24 h after pheophorb ide A administration (9 mg/kg intravenously) gave a selectivity ratio of 13.5:1 between tumour and surrounding tissue. Light of 660 mm and 1 00 J/cm(2) induced selective necrosis of the tumour. Six of nine rats Were cured in 120 days whereas all 36 control animals died within 35 d ays (P<0.01). The pancreas and hepatic pedicle were relatively unaffec ted by PDT, but the duodenum was injured.