When heartburn could be a sign of cancer
Just about everybody knows what heartburn feels like. From indigestion to pregnancy, it’s a common symptom. But you might not know that persistent heartburn can sometimes be a sign of something more serious.
Oesophageal cancer, which affects the food pipe leading from the throat to the stomach, is a relatively uncommon but devastating disease. Known risks for this type of cancer include the usual culprits- smoking, alcohol, and diet. And also heartburn. It's very rare, but a small proportion of people with long-term heartburn could be at risk of developing oesophageal cancer. This is why the NHS recommends that if you have chronic heartburn over 3 weeks or more, get it checked out by a GP.
But exactly how can heartburn lead to cancer? And what can research do about it? Here’s a rough guide to what we already know, and how we are helping.
From heartburn to cancer- and all the steps in between
Heartburn, or acid-reflux, is that familiar burning feeling caused when too much stomach acid escapes up into the oesophagus.
In a small proportion of people chronic acid-reflux can start to irritate and damage cells lining oesophagus, eventually causing the cells to change shape and grow abnormally. These cells start looking more like cells from the stomach and less like oesophageal cells- a condition called Barrett’s oesophagus.
Most people with Barrett’s can manage their condition through monitoring, treatments, and lifestyle changes, and that’s where the story ends. But if Barrett's goes undetected, the cells can sometimes continue to change until tumours eventually start to develop.
It’s worth noting that we’re talking about small numbers here. Just 5 to 10 per cent of people with persistent acid-reflux will develop Barrett’s, and just 5 to 10 per cent of those will go on to develop oesophageal cancer. In other words, the vast majority of people with heartburn do not develop oesophageal cancer.
But the disease can be tough on those that do. Although oesophageal cancer survival is improving in this country and has tripled since the 1970s, still fewer than 2 in 10 patients will survive 10 or more years.
Tracking the start of oesophageal cancer
It takes a long time and many different steps for a damaged oesophageal cell to change from being a healthy cell, to a Barrett’s cell, to a cancerous cell. Scientists don’t yet know all of these important steps, but Dr Benjamin Beck at the Université Libre de Bruxelles in Belgium wants to find out. In a new project he and his team are focusing on working out the cancer-causing genetic changes that happen during Barrett’s.
“Understanding exactly how oesophageal cancer starts is the cornerstone of developing new therapeutic strategies to beat the disease,” says Dr Beck.
“In this project we will use state-of-the-art ‘tracing’ experiments in genetically-engineered mice to follow the progress of cells in the food pipe- from the moment early cancer-causing genes are activated to the point full-blown tumours develop.”
“If we can identify exactly which genes are being activated at the very start, then we can work to develop brand new anticancer therapies to target them.”
By finding out the gene changes involved at the very earliest stages of the disease, Dr Beck’s research could also help identify genetic ‘flags’ to help predict who is more likely to develop oesophageal cancer, and when. Early diagnosis is key to making sure patients can receive the right treatment as soon as possible.
Improving oesophageal cancer treatment success
Oesophageal cancer can sometimes be hard to treat, and better treatments are needed to help ensure survival keeps on improving. This is where Dr Ludwig Dubois and his team at Maastricht University in the Netherlands come in.
Dr Dubois is focusing on improving treatment success rates. Radiotherapy is a standard treatment for oesophageal cancer, but its effectiveness is reduced in less well oxygenated tumour areas. “One of the important characteristics of oesophageal cancer is that the tumours often have regions of low oxygen concentration,” says Dr Dubois. “We think we can exploit this by designing new drugs which specifically target these regions.”
Dr Dubois is particularly interested in TH-302, a new drug which has been shown to kill cancer cells within regions of low oxygen. He thinks TH-302 might help radiotherapy get to these difficult parts of the oesophageal tumour, and enhance treatment success.
“We really believe that this combination treatment could enhance the chance of curing oesophageal cancer,” -Dr Ludwig Dubois
To investigate this idea, Dr Dubois is using samples from mice and patients with oesophageal tumours. “We really believe that this combination treatment could enhance the chance of curing oesophageal cancer,” says Dr Dubois. “But we also need to see if the combination of TH-302 with radiotherapy is safe for healthy tissues such as the lung and the oesophagus.”
“Finally, we want to investigate if imaging these low oxygen tumour regions before therapy might also help us predict treatment effectiveness.”
Photodynamic therapy success
Worldwide Cancer Research support is already helping patients at risk of oesophageal cancer. Along with other researchers, Professor Bown at University College London has spent many years developing an innovative form of treatment called photodynamic therapy (PDT). PDT uses light to draw a light-sensitive drug towards cancerous tissue. His Worldwide Cancer Research-funded work has helped ensure PDT is now available for patients with head and neck cancers, and can also be used to treat Barrett’s oesophagus.
You can read more about PDT, and how we helped Professor Bown’s work here.
The NHS recommends that if you’ve had heartburn most days for three weeks or more, then you should go to your GP for a check-up. Other warning signs along with heartburn can help give your GP a clearer idea of your condition. You can find out more here.
You can read more about our oesophageal cancer projects here.
Read more about heartburn treatment and causes on the NHS choices website here.