Introduction

The adoption of colorectal endoscopic submucosal dissection (ESD) as the main treatment for large colorectal lesions is still limited in the Western world. Through the implementation of novel strategies and training programs, ESD has been proved more effective than piecemeal endoscopic mucosal resection (EMR) for large colorectal lesions, without a significantly higher risk of adverse events, according to recent high-quality data. Reproducibility outside experts centers has been questioned.

Aims & Methods

Therefore, we evaluated results according to volume case load per year in a large multicentric prospective cohort of colorectal ESDs. Patients referred for colorectal ESD were consecutively included in this multicentric prospective cohort (FECCO NCT04592003) between 09/2019 and 09/2022. Participating centers were classified into low-volume (LV) (<50 ESDs/year), middle-volume (MV) (50-100 ESDs/year), and high-volume (HV) centers (>100 ESDs/year). Efficiency was assessed in terms of en bloc, R0, and curative resection rates and dissection speed, while rates of complications and need for surgery were the main safety outcomes. Both univariate and multivariate analyses were performed for our analysis.

Results

3770 colorectal ESDs performed in 13 centers by 29 operators were included. 62.4% of the lesions were located in the colon and 37.6% in the rectum. Median large and small lesion diameters were 50 mm and 40 mm, respectively. HV group performed significantly more colonic cases (68.6%) than MV and LV center groups (61.6% and 40.5%, respectively) (p<0,0001).
Lesions were significantly larger in HV and MV centers (50 x 40 mm for both) in comparison to LV centers (45 x 35 mm) (p<0,0001). The overall en bloc resection rate was 95.2%; HV centers achieved a significantly greater rate (96.3%) than MV and LV centers (92.9% and 93.9%, respectively) (p<0,01). Pooled R0 resection rate was 87.4%; it was better in HV centers than in MV and LV centers (88.7% vs 83.8% and 86.8%, respectively). Similarly, the curative resection rate, being overall 83.2%, was lower in MV centers (79%) in comparison to HV and LV groups (84.7% (p<0,01) and 82.5% (p= 0.10), respectively).
The median duration of procedure was 57 min (IQR 35-90) and was shorter in HV centers (48 min, IQR 30-80) than LV and MV group (75 min, IQR 45-120 and 70 min, IQR 42.8-120.5, respectively) (p<0,0001). Dissection speed was 28.7 mm2/min (IQR 16.8-45.8), being greater in HV centers (34.8 mm2/min, IQR 21.3-51.4) and lower in MV (22.9 mm2/min, IQR 14.7-34-5) (p<0,0001) and LV centers (18.1 mm2/min, IQR 10.5-28.6) (p<0,0001).
All three groups exceed the recommended thresholds of acceptability with satisfactory quickness. Globally, delayed bleeding and surgery due to complications occurred in 5.4% and 0.8% of cases, respectively, with no significant difference between the three groups. Perforation rate, being overall 9%, was higher in MV centers (11.1%) than LV and HV groups (7.5% (p= 0.02) and 8.7% (p= 0.06), respectively).
Multivariate analysis found that size >50 mm, poor maneuverability, recurrent and appendiceal lesions, but not volume of the center were risk factors for both R1 resection (p<0,001) and perforation (p<0,001) suggesting that differences of outcomes can be explained by lesion characteristics.

Conclusion

This study shows that, with appropriate training and organization, colorectal ESD can be widely implemented in the West with good outcomes even in not expert contests. Thus, under these conditions, ESD should be adopted as the first-line treatment for large colorectal lesions also in the Western world. Nevertheless, challenging lesions should still be referred to expert centers.