Clinically Relevant Improvement of Recurrence-free Survival with 5-Aminolevulinic Acid Induced Fluorescence Diagnosis in Patients with Superficial Bladder Tumors

Abstract

Fluorescence diagnosis induced by 5-aminolevulinic acid enables more thorough transurethral resection of superficial bladder carcinoma compared with conventional white light. We performed a prospective, single institution, randomized trial to investigate whether the residual tumor rate and long-term tumor recurrence can be decreased by fluorescence diagnosis. A total of 301 patients underwent transurethral resection of bladder tumors with white light or fluorescence diagnosis. Transurethral resection was repeated 5 to 6 weeks later to evaluate the residual tumor rate. To determine recurrence-free survival patient followup was performed every 3 months by white light cystoscopy and urine cytology. Recurrence-free survival was analyzed via Kaplan-Meier methods and multivariable Cox regression analysis. A total of 191 patients with superficial bladder carcinoma were available for efficacy analysis. The residual tumor rate was 25.2% in the white light arm versus 4.5% in the fluorescence diagnosis arm (p <0.0001). Median followup in the white light arm in 103 cases was 21.2 months (range 4 to 40) compared with 20.5 (range 3 to 40) in the 88 in the fluorescence diagnosis arm. Recurrence-free survival in the fluorescence diagnosis group was 89.6% after 12 and 24 months compared with 73.8% and 65.9%, respectively, in the white light group (p = 0.004). This superiority proved to be independent of risk group. The adjusted hazard ratio of fluorescence diagnosis versus white light transurethral resection was 0.33 (95% confidence interval 0.16 to 0.67). Fluorescence diagnosis is significantly superior to conventional white light transurethral resection with respect to the residual tumor rate and recurrence-free survival. The differences in recurrence-free survival imply that fluorescence diagnosis is a clinically relevant procedure for decreasing the number of tumor recurrences.