Mucosal ablation in Barrett's esophagus

[Endoscopic argon plasma thermo-coagulation of Barrett's esophagus using different powers: histopathological and post procedure symptons analysis]

OBJECTIVE

To establish the ideal power to be employed in order to get the effective ablation and the lowest rate of symptoms at argon plasma thermocoagulation in Barrett's esophagus (BE).

METHODS

Twenty-eight asymptomatic patients with BE, were randomly divided in two groups of different ablation powers, 50W or 70W. After endoscopic ablation and biopsies from the treated area for histological analyses, symptoms were evaluated through a questionnaire answered by phone.

RESULTS

Thirteen patients without specialized columnar metaplasia were excluded and the remaining fifteen patients, seven men (46,7%) and eight women (53,3%), with an average age of 53 years +10,4, composed the two groups: 10 patients at the 70W power and 5 at the 50W power group. There was no significant difference between the groups regarding age, BE extent, percentage of coagulated esophageal circumference and the duration of symptoms. Pain was the most important symptom, with a mean duration of 10,3 + 9,7 days. When power was compared to symptoms, although not statistically significant, a moderate negative correlation was noted. Endoscopic biopsies showed ablation restricted to the mucosa's superficial layer in 40% of the cases in the lower power group, and only 10% in the higher power group, although deeper layers of the mucosa were compromised. There were no statistical significant differences when comparing the different powers to the penetration through the mucosa's layers and the symptoms.

CONCLUSION

There are evidences that the 70W potency argon plasma coagulation for BE leads to a lower incidence of residual specialized columnar metaplasia under the new scamous epithelium.

Banding without resection (endoscopic mucosal ligation) as a novel approach for the ablation of short-segment Barrett's epithelium: results of a pilot study

OBJECTIVES

During an endoscopic variceal ligation, we banded a varix with an overlying tongue of Barrett's epithelium (BE). One month later, the tongue was no longer visible, suggesting that banding could be used to eradicate BE.

AIM

To assess the safety and efficacy of banding without resection (BWR) using a variceal banding device for eradicating BE.

METHODS

From April 2004 through September 2005, 30 patients with BE were treated with BWR plus omeprazole 20 mg t.i.d. BWR was repeated monthly until two consecutive endoscopic and histological examinations showed no BE. Thirty Barrett's patients treated with omeprazole 20 mg t.i.d. alone served as a control group.

RESULTS

The BWR treatment group comprised 29 patients with short-segment BE (SSBE) and one with long-segment disease, whereas all 30 of the control patients had SSBE. During a median follow-up of 16.9 months (range 10-24 months), complete eradication of BE was achieved in 29 of 30 patients (97%) in the BWR group. In contrast, BE persisted in all 30 control patients during the same period (P < 0.0005). The mean total number of bands applied per patient was 6.1 (range 1-14) and the mean number of sessions for complete eradication was 3.1 (range 1-7). Adverse events included only mild chest pain and dysphagia that resolved within days.

CONCLUSIONS

BWR appears to be a safe, effective, simple, and widely available technique for eradicating SSBE. This is a pilot study and we do not recommend the ablation of nondysplastic BE at this time. Further studies are needed.

Abnormal expression of biomarkers in incompletely ablated Barrett's esophagus

OBJECTIVE

The aim of this study was to evaluate expression of cancer risk-associated biomarkers in columnar epithelium at squamocolumnar junctions produced by an ablation procedure and proton pump inhibitors in incompletely ablated Barrett's esophagus (BE) patients that were nondysplastic prior to ablation.

SUMMARY BACKGROUND DATA

Ablation of BE to squamous epithelium is achievable by combining a re-injury method with acid suppression. We previously reported that, when there is complete ablation, the neo-squamous epithelium is normal histologically and in biomarker expression. However, squamous islands observed after prolonged use of PPIs were associated with abnormalities in p53 expression and Ki-67 labeling.

METHODS

Twenty-one nondysplastic BE cases with incomplete ablation were evaluated for the expression of Ki-67 (proliferation), cyclooxygenase-2 (COX-2), and p53 by immunohistochemistry.

RESULTS

Pre-ablation biopsies showed the normal staining patterns in columnar epithelium, ie, normal Ki-67 labeling, rare positive COX-2 staining of interstitial cells, and negative or mild staining for p53 in the majority of patients' biopsies. However, post-ablation biopsies demonstrated abnormal staining patterns in the glandular area at the new squamocolumnar junctions. In 13 of 21 post-ablation cases (62%), increased Ki-67 staining was seen in BE glands. In 8 of 21 patients (38%), increased COX-2 expression was seen in columnar epithelium. Similarly, in 8 of 21 post-ablation junctions (38%), there was increased p53 staining.

CONCLUSIONS

Our findings of increased expression of cancer-associated biomarkers in incompletely ablated BE patients raise a cautionary note regarding this procedure. We hypothesize that newly formed junctions contain cells undergoing replication, differentiation, etc, and are thus more susceptible to genomic damage.

Long-term follow-up after complete ablation of Barrett’s esophagus with argon plasma coagulation

AIM: To report the long-term outcome of patients after complete ablation of non-neoplastic Barrett’s esophagus (BE) with respect to BE relapse and development of intraepithelial neoplasia or esophageal adenocarcinoma.

METHODS: In 70 patients with histologically proven non-neoplastic BE, complete BE ablation was achieved by argon plasma coagulation (APC) and high-dose proton pump inhibitor therapy (120 mg omeprazole daily). Sixty-six patients (94.4%) underwent further surveillance endoscopy. At each surveillance endoscopy four-quadrant biopsies were taken from the neo-squamous epithelium at 2 cm intervals depending on the pre-treatment length of BE mucosa beginning at the neo-Z-line, and from any endoscopically suspicious lesion.

RESULTS: The median follow-up of 66 patients was 51 mo (range 9-85 mo) giving a total of 280.5 patient years. A mean of 6 biopsies were taken during surveillance endoscopies. In 13 patients (19.7%) tongues or islands suspicious for BE were found during endoscopy. In 8 of these patients (12.1%) non-neoplastic BE relapse was confirmed histologically giving a histological relapse rate of 3% per year. In none of the patients, intraepithelial neoplasia nor an esophageal adenocarcinoma was detected. Logistic regression analysis identified endoscopic detection of islands or tongues as the only positive predictor of BE relapse (P = 0.0004).

CONCLUSION: The long-term relapse rate of non-neoplastic BE following complete ablation with high-power APC is low (3% per year).

Barrett's esophagus and Barrett's carcinoma

The alarming rise in the incidence of esophageal adenocarcinomas in the Western world has focused interest on so-called Barrett's esophagus. Barrett's esophagus is characterized by specialized intestinal epithelium replacing the normal squamous epithelium in the distal esophagus and is considered a consequence of long-lasting and severe gastroesophageal reflux disease. A metaplasia-dysplasia-carcinoma sequence links Barrett's esophagus with adenocarcinoma of the distal esophagus (Barrett's cancer). Despite intensive research, many questions concerning the pathogenesis, diagnosis, and treatment of Barrett's esophagus and associated adenocarcinoma are still unanswered. Based on current data, the malignant progression of Barrett's esophagus cannot be substantially prevented by medical or surgical therapy for reflux. Although no firm data are available to show that surveillance strategies can reduce overall mortality from Barrett's cancer, early detection and cure are possible. Management of Barrett's esophagus and carcinoma is reviewed with reference to the sequence of disease from metaplasia to carcinoma.

Antireflux surgery for Barrett's oesophagus

Barrett's oesophagus is usually the result of severe reflux disease. Relief of reflux symptoms is the primary aim of treatment in patients with Barrett's oesophagus who do not have high-grade dysplasia. Some studies with medium-term (2-5 years) follow up show that antireflux surgery can provide good or excellent symptom control, with normal oesophageal acid exposure, in more than 90% of patients with Barrett's oesophagus. Antireflux surgery, but not medical therapy, can also reduce duodenal nonacid reflux to normal levels. There is no conclusive evidence that antireflux surgery can prevent the development of dysplasia or cancer, or that it can reliably induce regression of dysplasia, and patients with Barrett's oesophagus should therefore remain in a surveillance programme after operation. Some data suggest that antireflux surgery can prevent the development of intestinal metaplasia (IM) in patients with reflux disease but no IM. The combination of antireflux surgery plus an endoscopic ablation procedure is a promising treatment for patients with Barrett's oesophagus with low-grade dysplasia.