PHASE-I TRIAL OF PHOTODYNAMIC THERAPY IN THE TREATMENT OF RECURRENT SUPERFICIAL TRANSITIONAL-CELL CARCINOMA OF THE BLADDER

Objectives. A Phase I trial of photodynamic therapy (PDT) in the treat ment of superficial transitional cell carcinoma (TCC) of the bladder w as performed. Methods. Twenty patients with recurrent superficial TCC of the bladder after receiving a mean of 2.6 (range 1 to 6) courses of intravesical therapy were treated with PDT. Tt ie photosensitizer Pho tofrin II dose was 1.5 or 2.0 mg/kg. A 650-nm intravesical red laser w as used to activate the photosensitizer 2 days after administration of Photofrin II. A 0.01% intralipid solution was used as a bladder-filli ng medium to scatter light and achieve more homogeneous light distribu tion. Light doses from 5.1 to 25.6 J/cm(2) (total dosage 1500 to 5032 J) were used to illuminate the bladder. Results. Twenty patients under went 21 treatments with PDT. Complications included asymptomatic reflu x in 4 patients. One other patient, treated at the highest total light dose, experienced bladder contraction and fibrosis. Nine patients (45 %) had no tumor evident at cystoscopy, on random biopsies, or in urina ry cytology at the 3-month evaluation after treatment. Four patients r emained without recurrent disease for 23 to 56 months. Sixteen of 20 ( 80%) patients experienced recurrence, and 8 of the 16 underwent cystec tomy. Conclusions. An intravenous photosensitizer dose of 1.5 mg/kg Ph otofrin II followed by light energy in the range of 15 J/cm(2) (total light dose 2500 to 3250 J) was defined as a safe treatment parameter a nd resulted in tumor responses. With present technologies, administrat ion of PDT requires careful dosimetry.