Hexyl Aminolevulinate Fluorescence Cystoscopy: A New Diagnostic Tool for Photodiagnosis of Superficial Bladder Cancer—A multicenter study

Abstract
We examined the sensitivity and specificity of Hexvix (PhotoCure ASA, Oslo, Norway) hexyl aminolevulinate (HAL) fluorescence cystoscopy in patients with superficial bladder cancer. A total of 52 patients (38 men and 14 women) with a mean age of 72 years were investigated. HAL hydrochloride (100 mg dissolved in 50 ml phosphate buffer solution) (8 mM) was instilled into the bladder 1 hour prior to the endoscopic procedure. Cystoscopy was performed with the Storz D-light (Karl Storz, Tuttlingen, Germany) system, allowing inspection of the bladder wall under white and blue light (380 to 450 nm). A total of 422 biopsies obtained in fluorescing (165) and nonfluorescing (257) areas, including 5 random biopsies per patient, were analyzed to provide the best reference for the calculation of sensitivity and specificity. There were a total of 143 histologically verified tumors in 45 patients, including carcinoma in situ (CIS), Ta or T1 lesions. A total of 43 patients were diagnosed by fluorescence cystoscopy compared with 33 diagnosed by white light for 96% and 73% per-patient sensitivity, respectively. HAL cystoscopy was found particularly useful for finding CIS tumors. Of 13 patients with CIS tumors all except 1 were diagnosed or confirmed by HAL cystoscopy. HAL cystoscopy was well tolerated with no definite drug related adverse events reported, including effects on standard blood parameters. HAL fluorescence cystoscopy is a new, sensitive, promising diagnostic procedure that showed improved detection of bladder tumors, in particular CIS. The procedure is well tolerated and can easily be implemented in current clinical practice.
Keywords