ASSESSMENT OF SUBMUCOSAL LAYER QUALITY OF COLORECTAL EMR VERSUS ESD SPECIMENS – A PILOT STUDY

Aims Analysis of submucosal invasion depth is important to adequately predict lymph node metastasis risk after endoscopic resection of early colorectal cancer. Little is known about the quality of submucosal layer in specimens obtained by standard EMR or ESD. Here, we compare morphometric data on submucosal layer quality in routine histopathology specimens from EMR versus ESD.

Methods In this retrospective pilot study routine histopathology specimens were analyzed (6x EMR vs. 6x ESD – all right-sided colon). After selection to avoid possible artifacts (measurements not at the edges of the sections and preferably in areas with a longitudinal section) the EMR group comprised 18/278 (6.5%), the ESD group 34/381 (8.9%) of the routine tissue sections for morphometric analysis.

Results Sections were analyzed for homogeneity of submucosal layer thickness (i.e. variation coefficient), minimal and maximal submucosal thickness as well as for the fraction of submucosal layer thickness≥1000µm relative to the total area analyzed. Comparative analysis revealed significant differences in submucosal area thickness≥1000 μm (EMR vs. ESD: 91.2%±6.6 vs. 47.1%±10.6, p=0.018) and in the minimum submucosal thickness per tissue section analyzed (EMR vs. ESD: 933.7µm±125.1 vs. 319.0µm±123.6, p=0.009; [Figure 1]). No significant differences were observed for variation coefficient or maximum submucosal thickness.

Fig. 1

Conclusions In this small pilot series, specimens from EMR had a better preservation of the submucosal layer than those from ESD – possibly due to the different methods of specimen acquisition. The findings should be kept in mind when attempting to resect of lesions suspicious for submucosal invasive cancer.

Publication History

Article published online:
14 April 2022