En bloc resection significantly reduces NMIBC recurrence at 1 year

A multicentre, randomized, phase III trial conducted by researchers from the Chinese University of Hong Kong (CUHK) demonstrated a significant reduction in 1-year recurrence of non–muscle-invasive bladder cancer (NMIBC) with the use of en bloc vs standard resection (SR).

Conventionally, NMIBC is removed by transurethral standard resection (SR) in a piecemeal manner, which may result in floating tumour cells that are capable of reimplanting into the bladder wall, leading to disease recurrence. [Br J Urol 1962;34:215-220; Nat Rev Urol 2022;19:280-294] In addition, SR leads to fragmentation of tumour specimens, making it difficult to ascertain whether complete resection was achieved. Transurethral en bloc resection of the bladder tumour (ERBT) offers an alternative technique where the risk of tumour cell reimplantation may be reduced due to the tumour being removed in one piece. [J Urol 2000;163:878-879] Complete tumour resection can also be ascertained by histological means, as clear resection margins can be achieved in 94–99 percent of cases. [AME Med J 2020;5:29]

The present trial enrolled patients with NMIBC tumours ≤3 cm from 13 hospital in Hong Kong between April 2017 and December 2020. The patients were randomly assigned to receive ERBT (n=143) or SR (n=133). In the ERBT group, 88 percent of patients underwent ERBT successfully, 1.4 percent underwent modified ERBT, and the remaining 10.5 percent failed ERBT and crossed over to undergo SR. [Eur Urol 2024;doi:10.1016/j.eururo.2024.04.015]

The primary outcome of 1-year recurrence rate was 29 percent in the ERBT group and 38 percent in the SR group (p=0.007). None of the patients in the ERBT group developed disease progression at 1 year vs three patients in the SR group.

While median operative time was longer in the ERBT vs SR group (28 vs 22 minutes), all other perioperative outcomes, including detrusor muscle sampling rates, occurrence of obturator reflex, need of bladder irrigation, rates of postoperative mitomycin C instillation, and hospital stay, were similar between the two groups.

Within 30 days of operation, rates of any-grade complications, minor complications (grade 1/2), and major complications (grade 3/4) were similar in the two groups. Of note, there was one case of acute coronary syndrome and one case of pulmonary embolism after surgery in the ERBT group. None of the patients in the SR group developed major complications. There was no bladder perforation or mortality in either group. “Overall, the results showed that ERBT is safe and technically feasible,” commented the researchers.

“The multicentre setting of our study demonstrates the generalizability of ERBT across different surgeons and centres,” said one of the authors, Professor Chi-Fai Ng of the Department of Surgery at CUHK. “Proper surgical training and education are of utmost importance for effective dissemination of this new surgical technique.”

“Following a very comprehensive review of scientific evidence regarding ERBT, an international consensus statement on ERBT was published in 2020 and serves as a standard reference for any healthcare professionals who would like to adopt ERBT in their clinical practice,” added first author, Dr Jeremy Teoh of the Division of Urology at CUHK. [Eur Urol 2020;78:546-569] “This newly published randomized clinical trial shows the clinical benefits of ERBT, supporting it as the first-line surgical treatment for bladder cancer patients with non–muscle-invasive tumours of ≤3 cm.”