Risk of submucosal invasive cancer and high-grade dysplasia in a Multicentre Western Cohort of ESD treated colorectal lesion

Aims Although ESD is preferred for rectal adenomatous lesions larger than 20 mm, there is less agreement related to similar lesions located in the colon. Recent publications advocate that pEMR should be preferred, as lateral spreading tumours (LST) resected by pEMR in the right colon have a low rate of cancer (4.4%) [1,2]. However, Japanese studies showed a post ESD risk of submucosal invasive cancer and high-grade dysplasia of ~ 8-27% [3,4]. We set up a European multicenter retrospective study to assess the prevalence of submucosal invasive cancer (SMIC) and high-grade dysplasia (HGD) in a cohort of colorectal LST treated by ESD.

Methods European centers were invited to fill in a database of consecutive patients. Clinical variables related to patients and procedures were recorded, together with the center’s resection strategy for colorectal LST dissection (selective or universal colorectal ESD). The right colon (RC) was defined from the cecum to the transverse colon, and the left colon (LC) from the splenic flexure to the sigmoid. The prevalence of HGD and SMIC in the left and right colon and rectum (RE) were recorded and a logistic regression analysis was performed to test the data. Preliminary data are presented [1] [2] [3] [4].

Results Nine European centers provided data on 1359 lesions, 307 in the RC, 197 in the LC and 855 in RE. Two centers adopted universal ESD approach (n=267), 7 centers a universal Rectal ESD and selective colon ESD (n=1019) with one center initially adopting selective colorectal ESD (n=73).

There were statistically significant differences in the case mix of right, left colon and rectum lesions, with smaller lesions in the right and left colon when compared to rectum (RC 37.2 mm±16.1; LC 40.1mm±17.9; RE 49.2±28.3 p<0.001). More LST granular mixed nodular were represented in the rectum compared to the colon (RC 32.2%; LC 37.0%, RE 58.5% p<0.001) whereas sessile lesions were more frequent in the left colon and rectum (RC 9.1%, LC 31.7%, RE 15.1%). The left colon and rectum had higher prevalence of SMIC when compared to the right colon (RC 10.0%; LC 19.9%; RE 19.4% p≤0.01).

At multivariate analysis on the overall cohort (included variables: age, gender, dimensions, resection strategy, and morphology – LST classification, sessile, semi peduncolated), morphology other than LST Granular Homogeneous resulted as risk factor for covert SMIC (LST Granular Mixed Nodular Odds 1.08 – 95%CI 1.03-1.15; LST Non Granular Flat Elevated 1.10 – 95%CI 1.01-1.19; LST Non Granular Pseudo Depressed 1.17 – 95%CI 1.07-1.27; Semi-peduncolated 1.16 – 95%CI 1.00-1.36; Sessile, 1.15 – 95%CI 1.07-1.24), whereas the right colon resulted as a protective factor for covert SMIC (0.91 – 95%CI 0.85-0.97).

Conclusions Preliminary data show that LST, other than granular homogeneous type, have an increased risk of SMIC and that right colonic lesions have a lower risk of SMIC. Larger data are needed to further corroborate these results.

Publication History

Article published online:
27 March 2025

• References

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