Endoscopic submucosal dissection for early esophageal adenocarcinoma: low rates of metastases in mucosal cancers with poor differentiation

Background and aims: Endoscopic resection is accepted as standard treatment for intramucosal esophageal adenocarcinoma (EAC) that is well or moderately differentiated. Poor differentiation (PD) is judged as a risk factor for lymph node metastasis (LNM), and surgery is recommended. However, the evidence for this recommendation is weak. The aim of this study was to analyze the clinical course of patients after endoscopic resection of EAC with PD.

Methods: Patients undergoing endoscopic submucosal dissection for EAC were included from 16 German centers. Inclusion criteria were PD in the resection specimen, R0 resection, and endoscopic follow-up. Primary outcome was the metastasis rate during follow-up. Analysis was performed retrospectively in a prospectively collected database.

Results: Twenty-five patients with PD as single risk factor (group A) and 15 patients with PD and additional risk factors (submucosal invasion and/or lymphovascular invasion) (group B) were included. The metastasis rate was was 1 of 25 (4.0%; 95% CI, .4%-17.2%) in group A and 3 of 15 (20.0%; 95% CI, 6.0%-44.4%) in group B, respectively (P = .293). The rate of EAC-associated deaths was 1 of 25 (4%; 95% CI, .4%-17.2%) versus 3 of 15 (20%; 95% CI, 6.0%-44.4%) in group B (P = .293). The overall death rate was 7 of 25 (28.0%; 95% CI, 13.5%-47.3%) versus 3 of 15 (20%; 95% CI, 6.0%-44.4%) (P = .715). Median follow-up was 30 months (interquartile range, 15-53 months).

Conclusions: During long-term follow-up, the risk of metastasis is low after endoscopic resection of mucosal EAC with PD as a single risk factor. A conservative approach seems justified in this small patient group. However, the treatment strategy must be determined on an individualized basis until further prospective data are available.