HALO radiofrequency ablation (RFA)

HALO radiofrequency ablation (RFA) uses radio waves to destroy abnormal cells (dysplasia) in the lining of your food pipe (oesophagus). You might have this treatment to: 

  • remove pre-cancerous cells, or areas of cancer, without the need for major surgery  
  • treat the entire area of Barrett’s oesophagus

If you have gastric antral vascular ectasia (GAVE) in can be used to treat abnormal blood vessels in the stomach by using targeted heat to seal the blood vessels. 

The treatment is given during a gastroscopy procedure and you leave hospital the same day.

Not everyone can have a HALO procedure. People who can be offered the procedure:

  • have a small area affected
  • the tissue is only showing early changes
  • cannot have an operation

Risks and complications

Bleeding from the site of treatment

This may cause you to cough up or vomit (sick) blood. If you are vomiting large amounts of blood you may need another endoscopy to treat the bleeding site.

Hole or tear (perforation) in the food pipe wall

This affects about 1 in every 100 to 200 patients. You would need surgery to repair it.  


It is normal to feel chest pain for up to 1 week after the procedure and we advise trying painkillers, such as paracetamol, first and then a codeine tablet from your local pharmacy if this does not help. We will also give dietary advice to help you after the procedure.

Scar tissue

This can develop if a large area of tissue is removed. This may narrow your food pipe, making it difficult and painful to swallow. If this happens, contact us and another gastroscopy will be booked so that the narrowing can be stretched. We will also give steroid treatment to help prevent the scarring from forming.

HALO targets only the top layer of tissue lining the food pipe compared to an oesophagectomy which surgically cuts out a section, or all, of the oesophagus. If the abnormal cells have spread, you will need an oesophagectomy to make sure all abnormal cells have been removed.

Your doctor will discuss these risks with you again before asking you to sign a consent form.  

We want to involve you in decisions about your care and treatment. If you decide to go ahead, you will be asked to sign a consent form. This states that you agree to have the treatment and you understand what it involves. If you would like more information about our consent process, please speak to a member of staff caring for you.

Other treatment options

The only alternative treatment is an operation called an oesophagectomy. This is when part of your food pipe, including the area of abnormal cells, is removed. This is a major operation which usually means a long stay in hospital, including in intensive care. It can take months to recover fully from this operation.

If your health gets worse

If your health has got worse since your clinic appointment, call the clinical nurse specialist (CNS) helpline for advice on 020 7188 2673.

If you need to contact the consultant medical team, call the secretary on 020 7188 2491.

Resource number: 5147/VER2
Last reviewed: March 2023
Next review: March 2026

Contact us

If you need to change or cancel your appointment, call 020 7188 8887

For medical advice, contact the endoscopy unit Monday to Friday, 9am to 5pm.

Nurse in charge: 020 7188 7188 ext 54059

St Thomas' reception desk: 020 7188 7188 ext: 54046

In an emergency, out of hours (6pm until 8am the next day and on Saturday or Sunday) phone 020 7188 7188 and ask to be put through to the on-call gastroenterology registrar.

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

Is this health information page useful?