Endoscopy 2015; 47(08): 762
DOI: 10.1055/s-0034-1391841
Letters to the editor
© Georg Thieme Verlag KG Stuttgart · New York

Reply to Barret et al.

Jean Baptiste Chevaux
,
Pierre H. Deprez
Further Information

Publication History

Publication Date:
30 July 2015 (online)

We read with great interest the letter by Barret et al. and would like to respond to their concerns.

The aim of endoscopic submucosal dissection (ESD) in our study was to remove Barrett’s adenocarcinoma and not necessarily Barrett’s neoplasia, which can be “easily” treated with ablation techniques such as radiofrequency ablation (RFA) [1]. The main reason for the low rate of curative resection for neoplasia shown in our series (56 %) is that this was not the primary endpoint. Indeed most patients needed further endoscopic treatments for the remaining Barrett’s mucosa whether with or without low-grade and high-grade dysplasia. When Barrett’s mucosa was left in place, it was clearly visible, usually at the edges of the ESD (in our study, a median of 25 % of the esophageal circumference was not resected). Moreover, recurrent Barrett’s metaplasia or neoplasia was mainly seen at the neojunction, quite some distance from the upper (squamous) resected margin of large ESD specimens. The role of subsquamous extension of intestinal metaplasia may therefore be less than expected from previous reports [2].

To answer the specific question about the rate and role of buried glands after extensive ESD, no buried glands were ever found in the follow-up biopsies taken from the area of the ESD scar. This might be expected as, compared with ablative techniques and conventional endoscopic mucosal resection (EMR), ESD resection involves deeper layers, including the mucosa, the muscularis mucosae (m3 and m4 if a double muscularis mucosae was seen), and the superficial submucosa. Our rigorous follow-up protocol involved biopsies taken from the ESD scar and at the neojunction, and the follow-up period in our study now extends to more than 20 months. We do, however, agree that rigorous histological follow-up is required to search for buried metaplasia, even after extensive mucosal resection and ablation [3].

Barret et al. also suggest that currently available endoscopic diagnostic tools do not allow for accurate delimitation of Barrett’s neoplasia, therefore leading endoscopists to consider either en bloc resection of the entire Barrett’s mucosa, with larger security margins at least 10 mm distant from the visible lesion [2] [4] (albeit with high rates of esophageal stricture owing to the extent of resection performed), or systematic RFA of residual Barrett’s esophagus after resection of the visible lesion by ESD. This is of course true, especially for long-segment Barrett’s mucosa. Endoscopists should therefore discuss the treatment options with their patients taking into consideration extensive resection with high curative resection rates (such as the 85 % curative resection rate for adenocarcinoma shown in our study) and more limited resection combined with ablation techniques.

Endoscopic diagnostic tools such as volumetric laser endomicroscopy may, in the near future, help endoscopists appreciate the risk of buried glands [5]. Further comparative trials will be needed to compare full en bloc resection of Barrett’s neoplasia (including preventive measures for strictures) with more limited resection combined with ablation techniques and to evaluate the role of buried metaplasia. At the present time, we cannot prove that deeper and larger resections will abolish the risk of residual buried glands.

 
  • References

  • 1 Pouw RE, Wirths K, Eisendrath P et al. Efficacy of radiofrequency ablation combined with endoscopic resection for Barrett’s esophagus with early neoplasia. Clin Gastroenterol Hepatol 2010; 8: 23-29
  • 2 Anders M, Lucks Y, El-Masry MA et al. Subsquamous extension of intestinal metaplasia is detected in 98% of cases of neoplastic Barrett’s esophagus. Clin Gastroenterol Hepatol 2014; 12: 405-410
  • 3 Van Laethem JL, Peny MO, Salmon I et al. Intramucosal adenocarcinoma arising under squamous re-epithelialisation of Barrett’s oesophagus. Gut 2000; 46: 574-577
  • 4 Höbel S, Dautel P, Baumbach R et al. Single center experience of endoscopic submucosal dissection (ESD) in early Barrett’s adenocarcinoma. Surg Endosc Epub ahead of print 08.10.2014; DOI: DOI: 10.1007/s00464-014-3847-5.
  • 5 Leggett CL, Gorospe E, Owens VL et al. Volumetric laser endomicroscopy detects subsquamous Barrett’s adenocarcinoma. Am J Gastroenterol 2014; 109: 298-299