Article Text

PDF

Endoscopic therapy of Barrett’s: what more do we need to know?
  1. J-L Van Laethem,
  2. J Devière
  1. Department of Gastroenterology, Erasme University Hospital, Brussels, Belgium
  1. Correspondence to:
    Dr J-L Van Laethem
    Department of Gastroenterology, Erasme University Hospital, 808 Route de Lennik, Brussels, Belgium; jvlaetheulb.ac.be

Statistics from Altmetric.com

Results emerging from endoscopic treatments to ablate Barrett’s oesophagus indicate that APC alone or ALA-PDT in combination with APC achieves complete clearance of Barrett’s epithelium in approximately two thirds of patients

Over the past few years, different endoscopic ablative techniques have been used in combination with antireflux therapy with the aim of reversing Barrett’s oesophagus and replacing it with squamous epithelium. The end goal of these procedures is to impact directly on the risk of tumour development.

To date, most of the published results on ablative therapy in Barrett’s oesophagus have dealt with a single treatment modality, and long term results as well as the real impact on the course of the condition remain unanswered.

The most widely used and studied procedures are photochemical (that is, photodynamic therapy (PDT) using Photofin or more recently 5-aminolevulinic acid (5-ALA)1,2) and thermal (that is, argon plasma coagulation (APC)).3

The study by Hage and colleagues,4 in this issue of Gut, is the first to compare two modalities [see page 785]. This was a well designed, prospective, randomised, three arm study involving 40 patients with non or low dysplastic Barrett’s oesophagus, randomised to treatment with ALA-PDT as a single dose of 100 J/cm2 (n = 13), ALA-PDT as a fractionated dose of 20 and 100 J/cm2 (n = 13), or APC 65 W for two sessions (n = 14). All patients received omeprazole 40 mg daily. After the designated treatment, any residual Barrett’s oesophagus was treated with additional sessions of APC.

The end points of the study were endoscopic reduction of the Barrett’s oesophagus surface and the microscopic presence or absence of intestinal metaplasia at different time points (that is, six weeks and 6, 12, 18, and 24 months). In the setting of endoscopic therapy of Barrett’s oesophagus, complete histological ablation of specialised metaplastic epithelium should be considered the unique relevant end goal of these procedures as only complete histological clearance will influence the risk of cancer in this condition. Even in this scenario, only long term studies (more than five years) will tell us if this type of treatment is effective in preventing the need for surveillance and ultimately in reducing the risk of cancer development.

The results provided by the present randomised study are relatively similar to those reported in previous ones which assessed a single modality, particularly with regard to treatment procedures, median length of Barrett’s oesophagus (3 cm), proton pump inhibitor therapy, and duration of follow up (12 months).1–3

Clearly, there was no significant difference between the two procedures at six weeks, with a complete histological response rate of 33% and 36% for the ALA-PDT fractionated dose and APC, respectively. As additional treatment with APC was permitted in both groups for residual metaplastic mucosa, interpreting the 12 month results is difficult. However, it is interesting to note that residual Barrett’s oesophagus was observed in only 10% of the ALA-PDT group and in 33% of the APC group, although the difference was not significant as the number of patients enrolled was relatively small.

The results from the ALA-PDT group compare favourably with previous reports: PDT is effective in eradicating high grade dysplasia or superficial tumours in 90–100% of cases but squamous re-epithelialisation was found in only two thirds of patients and was incomplete in all.2,5 The rate of residual Barrett’s oesophagus after eradication using APC ranged from 0% to 68% in various series3,6,7 after a mean follow up period of approximately 12 months. It is not easy to explain this high variability which could depend on the technical procedure, length of the abnormal mucosa, and perhaps most importantly acid suppressive maintenance therapy.

In long term follow up studies (median follow up 36 months), we and others have clearly identified the length of the Barrett’s segment and normalisation of acid exposure as the only independent predictive factors for sustained long term re-epithelialisation.7,8 However, other factors may be involved such as biliary reflux, or microenvironmental or genetic abnormalities.7,9,10

In summary, the study of Hage et al confirms results emerging from endoscopic treatments to ablate Barrett’s oesophagus: APC alone or ALA-PDT in combination with APC achieves complete clearance of Barrett’s epithelium in approximately two thirds of patients. The direct impact on the cancer risk in Barrett’s oesophagus is unknown. Given the risk of developing adenocarcinoma arising under squamous re-epithelialisation,11,12 the potential complications of such endoscopic therapies, and the high cost of such management, we should follow the authors’ recommendations of not using these techniques routinely. On the other hand, these modalities, especially PDT and its newer development in photosensitisation, offer fascinating perspectives for the curative management of early neoplastic changes and severe dysplasia arising in Barrett’s oesophagus.

Finally, these experimental groups of patients, having already received treatment to eradicate Barrett’s oesophagus, should be monitored in order to obtain valuable clinical information on the rate of tumour development over the next 10 years. All of these patients should be followed up with further endoscopic evaluations at five and 10 years.

Results emerging from endoscopic treatments to ablate Barrett’s oesophagus indicate that APC alone or ALA-PDT in combination with APC achieves complete clearance of Barrett’s epithelium in approximately two thirds of patients

REFERENCES

View Abstract

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles