Efficacy of fluorescent cystoscopy-assisted transurethral resection in patients with non-muscle invasive bladder cancer and quality of surgery: post-hoc analysis of а prospective randomized study

Introduction: This paper aims to evaluate the influence of quality of transurethral resection in patients with non-muscle invasive bladder cancer on the benefit of fluorescent cystoscopy-assisted transurethral resection in the post hoc analysis of the single-center randomized controlled trial.

Material and methods: We retrospectively analyzed the results of the prospective randomized study assessing the efficacy of fluorescent cystoscopy-assisted transurethral resection. The quality of transurethral resection was defined on the basis of a separate retrospective study estimating the variability in recurrence risk for the individual surgeon. The subgroup analysis of fluorescent cystoscopy-assisted transurethral resection efficacy depending on surgical experience was performed.

Results: Of 377 eligible patients, transurethral resection was performed in 365 (97%) by surgeons with available grading information. Two 'experienced' surgeons performed 238 (63%) of all transurethral resections and three 'less experienced' surgeons completed 127 (34%) surgeries. The two surgical groups were comparable with respect to basic prognostic factors and subsequent therapy. The median follow-up was 56 months.In the total cohort of patients, fluorescent cystoscopy significantly decreased the risk of recurrence with hazard ratio 0.58 (p = 0.004). In the 'experienced surgeons' subgroup the benefit of fluorescent cystoscopy was not significant (hazard ratio 0.81, p = 0.34), whereas the 'less experienced' subgroup showed a marked difference in favor of fluorescent cystoscopy-assisted transurethral resection (hazard ratio 0.31, p = 0.001), with a P-value for interaction of 0.021.

Conclusions: Baseline quality of surgery may be a significant interacting factor affecting the magnitude of the benefit of fluorescent cystoscopy-assisted transurethral resection in patients with non-muscle invasive bladder cancer.