ESOU 2022: En Bloc Resection in Non-muscle Invasive Bladder Cancer: Where Do We Stand?

( The 2022 EAU Section of Oncological Urology (ESOU) Annual Meeting included a session on urothelial cancer and a presentation by Dr. Alberto Breda discussing the utilization of en bloc resection in non-muscle invasive bladder cancer (NMIBC). En bloc resection of bladder tumors has been hypothesized to lead to better pathological specimens, shorter operative and catheterization times, shorter hospital stays, less complications (ie. perforation), and better oncological outcomes:


Recently, the International Collaborative Consensus Statement on en-bloc resection of bladder tumor underlined the lack of high-quality prospective studies precluding the achievement of solid conclusion for en-bloc resection. Additionally, this statement concluded that a randomized clinical trial was necessary to confirm feasibility of en-bloc resection and resolve the controversy regarding the quality of the specimen compared to a TURBT specimen.1

Dr. Breda and his group subsequently designed a non-inferiority randomized clinical trial comparing TURBT and en-bloc resection of bladder tumor in terms of pathological diagnosis, surgical, and oncological outcomes. Interim results were previously presented at the EAU 2021 annual meeting and the final analysis is now under peer review. This study is a prospective, randomized trial enrolling patients diagnosed with bladder cancer and undergoing endoscopic intervention. Inclusion criteria were tumor size of <3 cm, and ≤3 lesions, and no sign of muscle invasion and/or ureteral involvement. The primary outcome is bladder cancer staging, and secondary outcomes include T1 substaging (microstaging systems T1a/b/c), intraoperative complications, rate of adjuvant treatment, postoperative complications, and oncologic outcomes. Overall, 300 subjects were included in the study with 1:1.5 treatment allocation for en-bloc resection of bladder tumor. An up to date flow diagram is as follows:


With regards to surgical outcomes, there was no difference in surgery duration (median, TURBT 30 min vs en-bloc resection 30 min, p = 0.129), obturator nerve reflex (TURBT 6.5% vs en-bloc resection 10.7%, p = 0.245), depth of resection (perforation: TURBT 14.8% vs 19% en-bloc resection, p=0.905), Clavien-Dindo complications (p = 0.535), catheter days (median TURBT 2 days vs en-bloc resection 2 days, p = 0.236), and hospitalization (median TURBT 2 days vs en-bloc resection 2 days, p = 0.629).

With regards to histological outcome, en bloc resection is non-inferior to TURBT in both detrusor muscle presence and staging of bladder cancer, with improvement in subtyping T1 disease for en-bloc resection:


After a median follow-up of 15 months (IQR 7-28), the 3 month recurrence rate for TURBT is 0% and for en bloc resection is 0.7% (p = 1.0), whereas the overall recurrence rate for TURBT is 17.6% and for en bloc resection is 12.9% (p = 0.3). As follows is the results based on type of energy used, including monopolar, bipolar, and Thulium laser:


Importantly, being a resident performing the case was not an independent predictor of perforation (vs attending urologist: B-coefficient 0.108 (-0.100-0.317, p = 0.308).

Dr. Breda concluded his presentation discussing the utility of en bloc resection for bladder tumors with the following take-home messages:

  • En bloc resection is non-inferior to TURBT for retrieving deep muscle and in bladder cancer staging, apart from the differentiation between T1 substaging
  • The intraoperative, postoperative, and oncological outcomes are comparable between the two techniques
  • Difference energies are available and each energy has its advantages and disadvantages leading to different indications in different settings
  • Residents are learning, and supervised residents are not dangerous to the patient

Presented by: Alberto Breda, MD, Head of Uro-Oncological Unit and Surgical Kidney Transplantation Team, Fundacio Puigvert, Universitat Autonoma de Barcelona, Barcelona, Spain

Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2022 EAU Section of Oncological Urology (ESOU) Hybrid Annual Meeting, Madrid, Spain, Fri, Jan 21 – Sun, Jan 23, 2022.


  1. Teoh JYC, MacLennan S, Chan VWS, et al. An International Collaborative Consensus Statement on En Bloc Resection of Bladder Tumour Incorporating Two Systematic Reviews, a Two-round Delphi Survey, and a Consensus Meeting. Eur Urol 2020 Oct;78(4):546-569.