Role of 5-aminolevulinic acid in the diagnosis and treatment of superficial bladder cancer: improvement in diagnostic sensitivity

Abstract

Objectives. To use 5-aminolevulinic acid (5-ALA) in diagnostic cystoscopy and during transurethral resection of the bladder (TURB) to treat transitional cell carcinoma. The efficacy of this new technique was compared with standard cystoscopy. Methods. The 5-ALA, instilled in the bladder 2 hours before cystoscopy, makes the pathologic tissue fluorescent when illuminated with blue light (375 to 400 nm). This allows a better recognition of the neoplastic forms for both diagnostic and therapeutic purposes during TURB. This method has been used since May 1997 on 49 patients in whom bladder tumor was diagnosed either immediately or during postchemotherapy follow-up. Results. One hundred seventy-nine biopsies were taken of fluorescent and nonfluorescent areas (3.5 per patient) to check the effectiveness of the new method compared with standard cystoscopy. A good correlation was found between 5-ALA cystoscopy and the histopathologic diagnosis, with a good sensitivity (87%). The 5-ALA cystoscopy allowed the diagnosis of a tumor in 24 patients with negative standard cystoscopic findings. Furthermore, 5-ALA cystoscopy detected 7 cases of carcinoma in situ. Neither local nor systemic (because of endovesical instillation) side effects were noted. Conclusions. We believe that 5-ALA could be routinely used in the diagnosis of superficial bladder tumors, as it was shown to improve the diagnostic sensitivity for carcinoma in situ and to reduce the risk of recurrence related to missed cancerous lesions or incomplete TURB.