Oral 5-aminolevulinic acid-mediated photodynamic diagnosis using fluorescence cystoscopy for non-muscle-invasive bladder cancer: A multicenter phase III study

ObjectiveTo confirm the reproducibility of the effectiveness and safety in photodynamic diagnosis of non-muscle-invasive bladder cancer using 5-aminolevulinic acid in a prospective multicenter non-randomized phase III trial. MethodsA total of 61 patients with primary or recurrent non-muscle-invasive bladder cancer were prospectively enrolled from five hospitals between May 2015 and March 2016. 5-Aminolevulinic acid (20 mg/kg) was orally administered 3 h before transurethral resection of bladder tumors using white light or fluorescent light. Of 60 evaluable patients, 511 specimens were obtained from tumor-suspicious lesions and normal-looking mucosa. The primary end-point was sensitivity. The secondary end-points were specificity, positive and negative predictive values, and safety. ResultsThe sensitivity of the fluorescent light source (79.6%) was significantly higher (P < 0.001) than that of the white light source (54.1%). In total, 25.4% (46/181) of tumor specimens were diagnosed as positive with only the fluorescent light source. In nine (15%) of 60 patients, the risk classification and recommended treatment after transurethral resection of bladder tumors were changed depending on the additional types of tumor diagnosed by the fluorescent light source. The specificity of the fluorescent light versus white light source was 80.6% versus 95.5%. No grade 4-5 adverse event was noted. Hypotension and urticaria were severe adverse events whose relationship to oral 5-aminolevulinic acid could not be excluded. ConclusionsThese findings confirm the diagnostic efficacy and safety of photodynamic diagnosis with 20 mg/kg of oral 5-aminolevulinic acid, and show that transurethral resection of bladder tumors with a fluorescent light source using oral 5-aminolevulinic acid is well tolerated.