Aims
The optimal endoscopic resection technique for non pedunculated colorectal polyps 15-20mm in size remained unclear. This study therefore aimed to evaluate the efficacy of snare tip precutting endoscopic mucosal resection (STP-EMR) compared to conventional EMR (C-EMR) for these lesions
Methods
This prospective randomized comparative study recruited 126 patients with 128 colorectal neoplasms of 15-20 mm in size and randomly assigned them in a 1:1 ratio to undergo STP-EMR or C-EMR at four university hospitals from June 2022 to November 2023. The primary outcomes were en bloc resection rate (EBR) and complete resection rate (CRR), determined by gastrointestinal pathologists based on histopathological findings. Adverse events and procedure time were also carefully analyzed.This prospective randomized comparative study recruited 126 patients with 128 colorectal neoplasms of 15-20 mm in size and randomly assigned them in a 1:1 ratio to undergo STP-EMR or C-EMR at four university hospitals from June 2022 to November 2023. The primary outcomes were en bloc resection rate (EBR) and complete resection rate (CRR), determined by gastrointestinal pathologists based on histopathological findings. Adverse events and procedure time were also carefully analyzed.
Results
A total of 128 eligible colorectal neoplasms were successfully resected using C-EMR and STP-EMR. The overall mean lesion size, EBR, and CRR were 17.2±1.9 mm, 78.9%(101/128), and 67.1%(86/128), respectively. The baseline characteristics such as location, size, morphology, and histologic findings of the polyps showed no significant differences between the two groups. The EBR and CRR were significantly higher in the STP-EMR group compared to the C-EMR group. Additionally, the mean total procedure time was significantly longer in the STP-EMR group. There were no significant differences in the post-procedural bleeding rate and hospital stays between the two groups. A perforation occurred in the STP-EMR group , but this was not statistically different from the C-EMR group.
Univariate analysis revealed that the resection method was the sole significant factor associated with both EBR and CRR. Pathologic findings and polyp type also significantly influenced CRR. In the multiple logistic regression analysis, the resection method remained the only significant factor of both EBR and CRR (OR 3.03, 95% CI 1.29-7.07, P=0.011).
| variables | C-EMR(n=65) | STP-EMR(n=63) | P value |
| En bloc resecion, no(%) | 46(70.8) | 55(87.3) | 0.022 |
| Number of resected pieces, mean(±SD) | 1.35±0.62 | 1.22±0.68 | 0.257 |
| Complete resection, no(%) | 38(58.5) | 48(76.2) | 0.033 |
|
Pathologic findings |
0.730 | ||
|
Serrated lesions |
22 (33.8) | 26 (41.3) | |
| Adenoma | 42 (64.6) | 36 (57.1) | |
| Carcinoma in situ | 1 (1.5) | 1 (1.6) | |
| Submucosal cancer | 0 | 0 | |
| Total procedure time, mean(±SD), min | 5.0 ± 3.9 | 8.1 ± 2.5 | <0.001 |
| Precut time, mean(±SD), min | 4.8 ± 1.8 | ||
| Admission rate, no(%) | 34 (52.3) | 48 (76.2) | 0.005 |
| Hospital stays, , mean (± SD) | 1.92 ± 0.973 | 2.14 ± 0.820 | 0.169 |
| post polypectomy bleeding, no(%) | 0.480 | ||
| Immediate(<24h) | 7 (10.8) | 6 (9.5) | |
| Delayed(≥24h) | 1 (1.5) | 0 | |
| Perforation, no(%) | 0 | 1 (1.6) | 0.492 |
Conclusions
STP-EMR seems to significantly improve en bloc and complete resection compared to C-EMR for non-pedunculated colorectal polyps of 15-20 mm, even though the procedure time of STP-EMR was longer than that of C-EMR.