Photothermal laser ablation of Barrett’s oesophagus: endoscopic and histological evidence of squamous re-epithelialisation

Abstract

Background-Barrett's oesophagus is acquired by severe gastro-oesophageal reflux and is a premalignant condition. Acid suppression or anti-reflux surgery alone do not cause significant regression of the metaplastic mucosa nor reduce the malignant potential. Recent reports have suggested that the combination of mucosal ablation with acid suppression may result in squamous regeneration. Aims-To destroy Barrett's mucosa by thermal ablation (in the setting of acid suppression) and so induce squamous regeneration. Patients-Sixteen patients with nondysplastic Barrett's oesophagus were recruited from a surveillance programme. All had been on a proton pump inhibitor. Methods-Atintervals, non-circumferential areas of columnar mucosa were ablated using the KTP laser. Acid suppression was obtained with 40 mg omeprazole daily. Multiple biopsy specimens were obtained for histological examination from ablated areas. Results-Ablation of all areas of glandular mucosa resulted in squamous regeneration. The number of treatments required depended on the length of the Barrett's segment. In 11 patients there was evidence of squamous regeneration over remaining Barrett's glands (in some of the posttreatment biopsy specimens) whilst in nine patients squamous metaplasia was seen within Barrett's glands. Conclusion-Mucosal ablation of Barrett's oesophagus by laser, in the setting of acid suppression, results in squamous regeneration (though some burying of Barrett's glands did occur). (Gut 1997; 41: 281-284)

Efficacy of proton pump inhibitors for cellular proliferation and apoptosis in Barrett's oesophagus with different mucin phenotypes

“…Therefore, endoscopic mucosal ablation is considered to be more suitable than PPI administration only for Barrett's regression therapy in cases with a high malignant potential. In combined treatment with mucosal ablation and PPI administration, however, the recurrence of columnar epithelium has been reported in about 50-70% of treated patients with Barrett's oesophagus, [37][38][39] suggesting that endoscopic treatment of Barrett's oesophagus may require more thorough and deeper ablation. Further studies on predictors for Barrett's regression and more effective regression therapy are warranted.…”

Results of Photodynamic Therapy in Barrett’s Esophagus: A Review

“…In nine patients who agreed to have the entire Barrett's segment treated, five had no endoscopic or biopsy evidence of Barrett's esophagus or intestinal metaplasia at the time of the report. More recently, Barham et al (36) described their results with thermal ablation in 16 patients with nondysplastic Barrett's esophagus treated with the potassium titanyl phosphate laser. However, during follow-up surveillance, subsquamous Barrett's mucosa was found in 11 of the 16 patients.…”

Molecular biomarkers and ablative therapies for Barrett’s esophagus

“…In a prospective evaluation of 58 patients with nondysplastic Barrett's esophagus treated with MPEC, 22% had residual Barrett's esophagus at 6 months follow up [33]. In a randomized trial of APC versus surveillance for nondysplastic Barrett esophagus after antireflux surgery, only 40% of patients had complete reversal of Barrett's esophagus at 5 years [27].…”

“…This mucosa is histopathologically similar to normal squamous epithelium, and it has therefore been assumed to have a reduced risk of cancer [22,23]. A variety of different ablation techniques have been developed, including argon plasma coagulation (APC) [24][25][26][27], photodynamic therapy (PDT) [28][29][30], multipolar electrocoagulation (MPEC) [31,32], Nd:YAG (neodymium-doped yttrium aluminum garnet) laser therapy [33][34][35], and more recently radiofrequency ablation (RFA) [36,37].…”