[A systematic review and meta-analysis to assess the recurrence-free survival in non-muscle invasive bladder cancer after transurethral resection guided by 5-aminolevulinic acid-induced photodynamic diagnosis compared with white-light transurethral resect]

Abstract

Introduction: We conducted a meta-analysis assessing the effect of photodynamic diagnosis (PDD) -guided transurethral resection of the bladder tumor (TURB) on the recurrence-free survival in patients with non-muscle invasive bladder cancer within prospective randomised trials that used 5-aminolevulinic acid as a photosensitizer.

Matherial and methods: Medical literature search was performed up to February 2016. Recurrence hazard ratios (HRs) and its 95% confidence intervals (CI) were calculated for each selected study with direct and indirect methods and the pooled estimates were obtained with random-effects model.

Results: Data from 5 prospective randomized trials with inclusion of 1089 patients were selected. Pooled estimate of recurrence HR was 0.71 (95% CI 0.48-1.04, p=0.08) with significant heterogeneity across selected publications: p=0,001; I2=78%. The subgroup analysis substantially reduced the heterogeneity: in subgroup comprising single/two-center studies or with moderate to high risk of bias or with long follow-up there was significant benefit of PDD-assisted TURBT (HR 0.51, 95% CI 0.38-0.69; p<0.0001), while in multicenter studies or those with low risk of bias or short follow-up the effect size was within the statistical error limits (HR 1.04, 95% CI 0.77-1.42, p=0.78).

Conclusions: Statistically significant benefit of PDD-guided TURBT over the white-light TURBT was limited to single/two-center studies or with moderate to high risk of bias or with long follow-up. True meaning of these finding it is not clear due to possibility of alternative explanations of identified differences. Generally there was low quality of evidence from significant proportion of studies and risk of publication bias.

Keywords: 5-aminolevulinic acid; non-muscle invasive bladder cancer; photodynamic diagnosis; recurrence-free survival; transurethral resection.