Concurrent bladder cancer in patients undergoing photodynamic diagnostic ureterorenoscopy: how many lesions do we miss under white light cystoscopy?

INTRODUCTION There is an ongoing debate on panurothelial changes in the upper and lower urinary tract as multifocal presentation of urothelial cancer is well recognised. Concurrent bladder cancer impacts the outcome of the upper urinary tract urothelial cancer treatment, while its detection still relies on the white light cystoscopy. MATERIAL AND METHODS We retrospectively reviewed all patients who underwent photodynamic diagnostic ureterorenoscopy, choosing those who had synchronous bladder biopsies. Each patient received 20 mg/kg body weight of oral 5-Aminolevulinic acid around 3-4 hours before endoscopy. All procedures were performed by a single endourologist experienced in photodynamic diagnosis and flexible ureterorenoscopy. RESULTS Between July 2009 and June 2013, 69 patients underwent bladder biopsies at the time of photodynamic diagnostic endoscopic inspection of the upper urinary tract. In total, 43.5% (30/69) patients were found to have bladder lesions, of which 43.3% (13/30) were proven to be carcinoma in situ. White light inspection of the bladder missed bladder cancer in 16 (23.1%) patients, of which 12 were carcinoma in situ. There were 14 bladder cancer lesions missed under white light which were concomitant to the upper urinary tract urothelial cancer. Twelve (17.4%) patients developed minor complications relevant to the photosensitizer. CONCLUSIONS The study raises a concern about missing small bladder cancer/carcinoma in situ lesions on the initial diagnosis or in surveillance of the upper urinary tract urothelial cancer. Higher than previously reported, the rate of concomitant bladder cancer may suggest utilisation of photodynamic diagnosis to ensure the cancer free status of the bladder, but this needs to be ratified in a multi-institutional randomised trial.