Objective Non-randomised studies suggest that endoscopic mucosal resection (EMR) is equally effective in removing large rectal adenomas as transanal endoscopic microsurgery (TEM), but EMR might be more cost-effective and safer. This trial compares the clinical outcome and cost-effectiveness of TEM and EMR for large rectal adenomas. Design Patients with rectal adenomas ≥3 cm, without malignant features, were randomised (1:1) to EMR or TEM, allowing endoscopic removal of residual adenoma at 3 months. Unexpected malignancies were excluded postrandomisation. Primary outcomes were recurrence within 24 months (aiming to demonstrate non-inferiority of EMR, upper limit 10%) and the number of recurrence-free days alive and out of hospital. Results Two hundred and four patients were treated in 18 university and community hospitals. Twenty-seven (13%) had unexpected cancer and were excluded from further analysis. Overall recurrence rates were 15% after EMR and 11% after TEM; statistical non-inferiority was not reached. The numbers of recurrence-free days alive and out of hospital were similar (EMR 609±209, TEM 652±188, p=0.16). Complications occurred in 18% (EMR) versus 26% (TEM) (p=0.23), with major complications occurring in 1% (EMR) versus 8% (TEM) (p=0.064). Quality-adjusted life years were equal in both groups. EMR was approximately €3000 cheaper and therefore more cost-effective. Conclusion Under the statistical assumptions of this study, non-inferiority of EMR could not be demonstrated. However, EMR may have potential as the primary method of choice due to a tendency of lower complication rates and a better cost-effectiveness ratio. The high rate of unexpected cancers should be dealt with in further studies.

中文翻译：

---

经肛门内镜显微手术与内镜黏膜切除术治疗大直肠腺瘤的随机对照试验（TREND 研究）

目的 非随机研究表明，内镜下黏膜切除术 (EMR) 在切除大直肠腺瘤方面与经肛门内镜显微手术 (TEM) 一样有效，但 EMR 可能更具成本效益且更安全。该试验比较了 TEM 和 EMR 治疗大直肠腺瘤的临床结果和成本效益。设计 直肠腺瘤 ≥ 3 cm，无恶性特征的患者被随机 (1:1) 接受 EMR 或 TEM，允许在 3 个月时内镜下切除残留的腺瘤。随机化后排除意外的恶性肿瘤。主要结果是 24 个月内的复发（旨在证明 EMR 的非劣效性，上限为 10%）以及存活和出院的无复发天数。结果 204 名患者在 18 所大学和社区医院接受治疗。二十七人 (13%) 患有意外癌症并被排除在进一步分析之外。EMR 后总体复发率为 15%，TEM 后总体复发率为 11%；没有达到统计上的非劣效性。存活和出院的无复发天数相似（EMR 609±209，TEM 652±188，p=0.16）。并发症发生率为 18% (EMR) 与 26% (TEM) (p=0.23)，主要并发症发生率为 1% (EMR) 与 8% (TEM) (p=0.064)。两组的质量调整生命年相等。EMR 大约便宜 3000 欧元，因此更具成本效益。结论 在本研究的统计假设下，无法证明 EMR 的非劣效性。然而，由于并发症发生率更低和成本效益比更好，EMR 可能有潜力成为首选的方法。