BARRETT'S OESOPHAGUS RFA
THE HALO SYSTEM AND CANCER PREVENTION

Barrett's oesophagus is a pre-cancerous condition where the normal squamous lining of the lower oesophagus is replaced by intestinal-type columnar epithelium — driven by chronic acid reflux. The risk of progression to oesophageal adenocarcinoma increases with the degree of dysplasia.

“Barrett's oesophagus RFA is about cancer prevention — not cancer treatment. The goal is to destroy the abnormal lining before it becomes invasive cancer. This is one of the few situations in medicine where we can actually see and treat a cancer precursor, and HALO RFA has made this practical, safe, and highly effective.”

• No Dysplasia: Surveillance Without Ablation

  Barrett's without dysplasia has a relatively low annual cancer risk (~0.3–0.5%). Standard management is endoscopic surveillance every 3–5 years. RFA is not typically recommended for non-dysplastic Barrett's, though research on this question continues.

• Low-Grade Dysplasia (LGD): RFA Now Recommended

  Confirmed LGD (by two expert pathologists) carries an annual cancer progression risk of approximately 1.5–2%. ACG and ESGE guidelines now recommend RFA for confirmed persistent LGD — following the SURF trial (de Matos Neto et al.) showing significantly lower cancer progression in ablated vs surveilled patients.

• High-Grade Dysplasia (HGD): RFA Standard of Care

  Barrett's with HGD progresses to cancer in 5–10% of patients per year. RFA is the guideline standard for non-nodular HGD. For nodular or raised HGD, EMR (endoscopic mucosal resection) is performed first to remove the nodular lesion and obtain histology, then RFA ablates the remaining flat Barrett's field.

The HALO system (Medtronic/Barrx) uses two complementary devices for complete Barrett's segment ablation.

• HALO360: Circumferential Ablation

  A balloon-based catheter inflated to the oesophageal diameter, with a 3 cm circumferential RFA electrode array on its surface. The balloon is inflated, the electrode applies energy (10–12 J/cm²) to the full circumference of the oesophageal wall in a 3 cm segment. Repositioned and re-applied to treat the full Barrett's length. Treats the entire mucosal circumference in each position — the appropriate device for first-treatment ablation of a long Barrett's segment.

• HALO90: Focal Ablation

  A smaller paddle electrode mounted on the tip of the endoscope — applies focal RFA to a 2.0 × 1.5 cm area at a time. Used for: residual islands of Barrett's mucosa after HALO360 treatment; tongues or patches of residual Barrett's at follow-up endoscopy; short-segment or focal Barrett's where circumferential treatment is not needed. Multiple spot applications are made at each follow-up endoscopy to achieve complete clearance.

The AIM Dysplasia Trial (Shaheen et al., NEJM 2009) is the pivotal RCT that established HALO RFA as the standard of care for Barrett's HGD and LGD.

How a typical Barrett's HGD ablation programme is structured over multiple sessions.

1. 1

   Step 1: Staging Endoscopy and EMR for Nodular Lesions

   Careful endoscopic mapping with high-resolution white-light and chromoendoscopy (or narrow-band imaging). Any raised or nodular areas must be removed by EMR before RFA — providing definitive pathological staging and ensuring no submucosal disease is present. Flat residual Barrett's is then the target for HALO RFA.

2. 2

   Step 2: HALO360 Circumferential Ablation (Session 1 or 2)

   HALO360 balloon catheter inflated in the oesophagus. Stepped ablation of the full Barrett's segment from the gastro-oesophageal junction proximally. Each position receives two energy applications. Total treatment covers the full Barrett's length. Session takes 20–40 minutes. Patient discharged same day with proton pump inhibitor therapy.

3. 3

   Step 3: Reassessment Endoscopy (8–12 Weeks)

   Endoscopy confirms sloughed Barrett's mucosa has healed (replaced by squamous epithelium) and identifies any residual islands. Biopsies confirm degree of residual Barrett's. If significant residual disease: repeat HALO360. Focal residual patches: HALO90 treatment in same session.

4. 4

   Step 4: HALO90 Focal Ablation Sessions (As Needed)

   HALO90 paddle electrode treats residual Barrett's islands identified at reassessment endoscopy. Multiple focal applications at each session. Repeat every 8–12 weeks until CE-IM achieved. Most patients achieve CE-IM after 2–4 total sessions.

5. 5

   Step 5: Surveillance After CE-IM

   After confirmed CE-IM (all biopsies negative for intestinal metaplasia on two consecutive endoscopies): surveillance endoscopy every 6–12 months for 2 years, then every 1–3 years. Barrett's can recur, particularly at the gastro-oesophageal junction — the squamocolumnar junction requires biopsy at every surveillance visit. PPI therapy continued lifelong.

Related resources for Barrett's oesophagus and oesophageal cancer.

Frequently Asked Questions

Common questions about Barrett's RFA.