The prognosis of nonresectable cholangiocarcinoma is dismal, and in Bismuth type III and IV tumors relief of jaundice is seldom achieved, despite successful endoprosthesis insertion. Therefore, we evaluated additional photodynamic therapy in patients who failed to respond to endoprostheses insertion. All patients showed good clinical results in regard to jaundice, quality of life; and survival time (median, 439 days). Before initiating a randomized multicenter trial we wanted to evaluate these preliminary results in a greater number of patients. Twenty-one patients underwent photodynamic therapy in addition to endoscopic drainage. The hematoporphyrin derivative Photofrin was infused intravenously (2 mg/kg body weight), and intraluminal photoactivation was performed 2 days later. Bilirubin decreased from a mean level of 201.26 +/- 189.25 micromol/l after stenting alone to 68.87 +/- 78.27 micromol/l (P = 0.0051), and the Karnofsky index improved from 49.04% +/- 28.79% to 72.85 +/- 19.01 (P = 0.003). Thirteen patients have died and 8 patients are still alive, with a follow-up period of 82-739 days. The 6-month survival time is 95%. Similar results were obtained by another group, with 75% overall (stage M1 and M0) survival after 6 months and beyond 80% for stage M0. Other authors treated 7 patients and saw a remarkable reduction of bile duct stenosis and bilirubin decrease in all patients.