Potential candidates for en bloc resection among patients with primary and recurrent bladder tumours

Transurethral resection (TURB) is the gold standard treatment for non-muscle invasive bladder cancer (NMIBC). However, conventional TURB is possibly part of the mechanism leading to the high recurrence rate in NMIBC and the need for repeated procedures, as the method with piecemeal resection of the tumour violates basic oncological principles and compromises pathological examination. En bloc resection (EBR) could potentially overcome these flaws by improving pathological quality and thereby reducing the need for re-resections and could potentially also lower the risk of tumour seeding leading to early recurrences. With this study, we aimed to evaluate tumour characteristics in a consecutive cohort of patients undergoing conventional TURB in order to estimate the proportion of procedures eligible for EBR, findings at re-resection, and early recurrence rate.

All TURBs performed at a single large University Hospital in a 12 month period were manually reviewed. Based on tumour size and appearance, patients were registered as candidates or non-candidate for EBR.

A total of 600 TURBs were reviewed. Overall, 25% of procedures were found to be eligible for EBR. The most frequent reason for not being a candidate was tumour diameter <1 cm. Re-resections were done after 10.5% of the procedures, where the residual tumour was found in 28.6% of these. Within 6 months, 21.2% had a recurrence.

We found approximately 25% of all TURBs to be eligible for EBR. Based on a relatively low recurrence rate, we conclude that future studies on EBR with recurrence rate as the primary endpoint will require large patient cohorts.