Cheap drug could protect thousands of long-term heartburn sufferers from deadly oesophageal cancer
A widely available diabetes drug that costs just 2p per tablet could cut the risk of one of the world’s deadliest cancers, according to a new study.
Metformin is already taken by millions to control blood sugar levels in type 2 diabetes.
Now leading oncologists believe it could also reduce the risk of oesophageal cancer by more than a third.
Publishing their findings in the journal JAMA Network Open, the researchers said it’s possible those most at risk of the disease – such as those who suffer from long term acid reflux – could in future be given the drug to protect against the disease.
Professor Shai–Hau Xie, an expert in gastrointestinal cancers, said: ‘From a clinical perspective, the observed association between metformin use and a significantly decreased risk of oesophageal cancer suggests a possible role for this drug in cancer prevention and treatment.’
Oesophageal cancer – cancer of the food pipe – is on the rise and is closely linked with risk factors such as obesity, poor diet, smoking, alcohol and acid reflux.
Those with Barret’s Oesophagus, a condition where cells in the the oesophagus grown abnormally sometimes as a result of long–term acid reflux, are also at an increased risk of the disease.
Metformin has been looked at as a potential treatment because studies suggest it can block the reproduction of cancer cells. The drug lowers levels of insulin, a hormone which helps malignant cells multiply.
Metformin, a diabetes drug that costs as little as 2p a pill, could cut the risk of oesophageal cancer by more than a third, a study suggested
Previous research has found it may also help prevent prostate cancer.
In the latest study, experts at Karolinska University Hospital, Stockholm, tracked over 13,000 oesophageal cancer patients matched with controls from 1994 and 2023.
Patients were enrolled on the Nordic Gastric and Oesophageal tumour study carried out in Denmark, Finland Iceland, Norway and Sweden.
Results were adjusted for potential confounding factors such as tobacco use, alcohol consumption, use of anti-inflammatory painkillers like ibuprofen and use of statins.
On average, patients were diagnosed with the deadly disease at around 70 years old, with the majority having smoked and drank heavily before their diagnosis compared with control participant.
Of the 13,050 cancer patients included in the final study, 725 – or just under six per cent – were metformin users.
By comparison around eight per cent of cancer-free participants were on the blood-sugar lowering drug, which researchers said could be protecting them against the disease.
The researchers concluded metformin could lower the risk of developing the deadly disease by an impressive 36 per cent, compared with non-use.
Persistent acid reflux is one of the most common symptoms of esophageal cancer
Surprisingly, metformin use was associated with lower odds of oesophageal squamous cell carcinoma (OSCC) regardless of sex, age, smoking status, alcohol consumption and use of NSAIDs and statins.
But the odds were especially lower in participants with a higher dose of the drug, defined as more than 1,278 daily doses over a five year period.
The team concluded: ‘The findings provide a rationale for exploring metformin as a preventive option in high-risk individuals, for example those with precancerous lesions.
‘The results also suggest a value of examining whether metformin medication after curative treatment for OSCC may improve survival.’
At present, the majority of patients who undergo curative treatment for the cancer – such as surgery – experience tumour recurrence leading to death just a few years after the treatment.
‘Adjuvant treatment with metformin could potentially reduce this risk,’ the researchers concluded.
‘However, current evidence remains limited and before metformin may be recommended for these purposes, additional observational research followed by clinical trials are needed.’
In the UK 9,300 people are diagnosed with oesophageal cancer a year, according to Cancer Research.
The disease is difficult to detect because the symptoms for the cancer are not easily recognisable – and can be mistaken for indigestion – until it is at an advanced stage.
Acid reflux – which occurs when stomach acid travels back up the oesophagus, irritating he lining of the gastric tract and increasing the risk of abnormal cell growth – has long been linked with an increased risk of the disease but the new finding could help protect those suffering from recurring heartburn.
