En-bloc resection of urinary bladder tumour - a prospective controlled multicentre observational study.

Introduction: Transurethral resection of bladder tumour (TURBT) is one of the most commonly performed urologic procedures. Because of the shortcomings of conventional TURBT, the en-bloc resection concept was created.

Aim: To analyse the influence of en-bloc technique on surgical and oncological outcomes of TURBT performed with electric current.

Material and methods: This non-randomized, prospective controlled multicentre study enrolled 427 consecutive patients undergoing TURBT performed by five experienced endourologists in five academic institutions. Choice of procedure was at the discretion of the surgeon. The vast majority of patients underwent monopolar resection. The en-bloc procedure was performed with Collin's knife or the classic resection loop. Study end-points were surgery, catheterization and hospitalization time, presence of muscularis propria (MP) in the specimen and 3-month recurrence-free survival (RFS).

Results: The study included 427 (274 conventional TURBT vs. 153 en-bloc) patients with mean age of 69 years (range: 18-99). There were more cases with MP present in the specimen in the en-bloc group (91.3% vs. 75.5%; p < 0.001). Surgery and hospitalization times were statistically shorter in the en-bloc group (both p < 0.05). A borderline significant difference was noted when the number of residual tumours in reTURBTs was analysed, with fewer cases of residual tumour in the en-bloc group (p = 0.051). RFS at 3 months was higher in the en-bloc group (88.4% vs. 80.1%; p = 0.027). After propensity score matching, differences in MP presence, hospitalization time and 3-month RFS status remained statistically significant.

Conclusions: When compared to conventional TURBT, en-bloc resection of bladder tumour is associated with higher percentage of MP presence in histopathological specimen, higher 3-month RFS and shorter hospitalization time.