Clinical trials have shown that hexaminolevulinate (HAL) fluorescence cystoscopy improves the detection of bladder tumors compared with standard white-light cystoscopy, resulting in more efficacious treatment. However, some recent meta-analyses report controversially on recurrence-free rates with this procedure. A systematic review of literature was performed from December 2014 to January 2015 using the PubMed, Embase and Cochrane databases for controlled trials on photodynamic diagnosis (PDD) with HAL. A total of 154 publications were found up to January 2015. Three of the authors separately reviewed the records to evaluate eligibility and methodological quality of clinical trials. A total of 16 publications were considered eligible for analysis. HAL-PDD-guided cystoscopy increased overall tumor detection rate (proportion difference 19%, 95% confidence interval [CI] 0.152-0.236) although the benefit was particularly significant in patients with carcinoma in situ (CIS) lesion (proportion difference 15.7%, 95% CI 0.069-0.245) and was reduced in papillary lesions (Ta proportion difference 5.9%, 95% CI 0.014-0.103 and T1 proportion difference 1.2%, 95% CI 0.033-0.057). Moreover, there were 15% of patients (95% CI 0.098-0.211) with at least one additional tumor seen with PDD. With regard to recurrence rates, the data sample was insufficient for a statistical analysis, although the evaluation of raw data showed a trend in favor of HAL-PDD. This meta-analysis confirms the increased tumor detection rate by HAL-PDD with a most pronounced benefit for CIS lesion.
Keywords: bladder cancer; hexaminolevulinate; meta-analysis; photodynamic diagnosis; tumor detection.