Bladder cancer is a common urological malignancy, with around 610,000 new cases and 220,000 deaths worldwide in 2022. Approximately 75% of these cases are non-muscle-invasive bladder cancer (NMIBC). The conventional method for treating NMIBC is standard resection (SR), performed transurethrally, where the bladder tumour is removed in a piecemeal manner. However, SR has limitations, with recurrence rates ranging from 15% to 61% at one year and 31% to 78% at five years. To address these challenges, en bloc resection of the bladder tumour (ERBT) has been proposed as an alternative technique that may offer improved oncological control. In SR, the piecemeal approach can cause tumour fragments to float within the bladder, increasing the risk of tumour cell reimplantation, which contributes to high recurrence rates. Additionally, tumour specimens are fragmented, making it difficult to assess whether a complete resection has been achieved. In fact, second-look transurethral resection often reveals residual disease in 17–67% of Ta cases and 20–71% of T1 cases. By contrast, ERBT involves removing the tumour in one piece, potentially reducing the risk of tumour seeding. Histological analysis can confirm clear resection margins in 94–99% of cases, providing more confidence that a complete resection has been achieved. This phase three, multicentre, randomised trial aimed to compare the one-year recurrence rate of NMIBC patients treated with ERBT versus SR, focusing on tumours of up to 3cm. The results showed that ERBT significantly reduced the one-year recurrence rate compared to SR. The technical success rate for ERBT was 88%, with the remaining 12% of patients requiring conversion to SR due to technical difficulties, such as challenging tumour locations or characteristics. Despite these challenges, the significant reduction in recurrence persisted in the intention-to-treat analysis. While no significant difference was observed in the one-year progression rate between the ERBT and SR groups (p=0.065), this secondary outcome was not the primary focus of the study, and the sample size was not powered to detect such differences. Additionally, the ERBT group had a slightly longer median operative time than the SR group (by six minutes), but other perioperative and safety outcomes were comparable between the two techniques, indicating that ERBT is both safe and feasible in a multicentre setting. Other studies have also explored the potential benefits of ERBT. For instance, Gallioli et al. conducted a randomised trial with 300 patients, demonstrating that ERBT was non-inferior to SR in terms of detrusor muscle presence. However, the recurrence rates did not reach statistical significance. Similarly, a study by D’Andrea et al. found that ERBT was superior in detrusor muscle presence but showed no difference in recurrence rates after a median follow-up of 13 months. These variations may be attributed to differences in surgical quality and postoperative treatments like intravesical chemotherapy. ERBT offers a more systematic approach to tumour resection, allowing for clear delineation of the margins and reducing the risk of incomplete resection. In cases where positive resection margins were identified, second-look transurethral resection revealed residual disease, supporting the use of margin evaluation to guide further treatment. In conclusion, this study is the first multicentre trial to demonstrate a significant reduction in the one-year recurrence rate with ERBT compared to SR in NMIBC patients with tumours up to 3cm. The results indicate that ERBT is safe, generalisable, and offers a promising alternative to SR, making it a viable first-line treatment for these patients. However, further research is needed to assess the long-term impact of ERBT on disease progression and to standardise its use in clinical practice.
Transurethral en bloc resection versus standard resection of bladder tumour
Reviewed by Asif H Ansari
Transurethral en bloc resection versus standard resection of bladder tumour: a randomised, multicentre, phase 3 trial.
