2 The procedure

2.1 Indications and current treatments

2.1.1

Barrett's oesophagus is a condition characterised by abnormal epithelium of the oesophagus. In some patients, Barrett's oesophagus may progress, through metaplasia and dysplasia, to oesophageal adenocarcinoma. Cancer risk is higher for patients with high-grade dysplasia (HGD; some of whom may already have developed early-stage cancer) and lower for patients with low-grade dysplasia (LGD) or no dysplasia.

2.1.2

Patients with HGD are usually offered oesophagectomy, or frequent endoscopic surveillance and re-biopsy (with the aim of detecting neoplastic changes early). Endoscopic treatments that aim to remove or ablate abnormal epithelium have also been developed, including endoscopic mucosal resection and photodynamic therapy.

2.1.3

Patients with LGD or no dysplasia are usually offered regular endoscopic surveillance and re-biopsy (with the aim of detecting potential progression to HGD or cancer).

2.2 Outline of the procedure

2.2.1

The aim of radiofrequency ablation (RFA) is to destroy the Barrett's epithelium in order to allow re-epithelialisation with squamous epithelium.

2.2.2

The procedure is carried out with the patient under conscious sedation, usually in an outpatient setting. Using endoscopic visualisation, an appropriately sized RFA probe is inserted into the oesophagus and advanced to the target area. Controlled pulses of RF energy are delivered to thermally ablate a thin epithelial layer in the affected areas. RFA is sometimes used after previous endoscopic mucosal resection.

2.2.3

If follow-up endoscopy and re-biopsy show residual Barrett's changes, repeat treatment sessions may be necessary.

2.3 Efficacy

Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview.

2.3.1

A randomised controlled trial (RCT) of 127 patients (63 with HGD and 64 with LGD) treated by RFA or a sham procedure reported complete eradication of Barrett's oesophagus in 77% (65 out of 84) and 2% (1 out of 43) of patients respectively at 12-month follow-up (p<0.001).

2.3.2

In the same RCT, among patients with HGD, fewer RFA-treated patients progressed to cancer at 12-month follow-up (2% [1 out of 42]) compared with those in the sham group (19% [4 out of 21]; p=0.04).

2.3.3

A register of 142 patients with HGD reported efficacy data on 92 patients with at least 1 follow-up endoscopy. At a median 1-year follow-up, HGD resolution had occurred in 90% (83 out of 92) of patients; 80% (74 out of 92) had no dysplasia (HGD or LGD) and 54% (50 out of 92) had no Barrett's at all.

2.3.4

The Specialist Advisers listed key efficacy outcomes as eradication of metaplasia and dysplasia, relapse rate and reduction in development of cancer.

2.4 Safety

2.4.1

Oesophageal stricture was reported in 6% (5 out of 84) of patients treated by RFA in the RCT of 127 patients (successfully treated by endoscopic dilatation) and 8 patients (denominator not stated) from a register of 106 patients treated by RFA (timing of events and management not stated).

2.4.2

Buried glandular mucosa detected on surveillance biopsy was reported in 15% (4 out of 27) of patients 6 to 12 weeks after RFA (precise timing of detection not stated) in a case series of 27 patients. All were treated with additional RFA. One buried glandular mucosa was reported in neosquamous epithelium among 1,475 biopsies (less than 1%) in a case series of 44 patients (subsequent treatment not described).

2.4.3

In the RCT of 127 patients, 1 patient developed new-onset chest pain and 1 patient developed chest discomfort and nausea. Both patients required overnight admission to hospital.

2.4.4

The Specialist Advisers listed anecdotal adverse events as dysphagia, minor bleeding, oesophageal perforation and pain (such as retrosternal pain).