A throat spray has been developed to spot cancer of the oesophagus at an early stage.
The disease, which killed Morse star John Thaw, is one of the most deadly cancers because it is often missed or wrongly diagnosed until too late.
Current methods used to detect it can be inaccurate, so many patients are given unnecessary invasive treatment including removal of their oesophagus, the ‘food pipe’ that connects the throat to the stomach.
Early detection key: If caught early, the cancerous cells can be zapped with an electric current which kills them without surgery.
Now scientists have developed a fluorescent dye spray which sticks to healthy cells in the oesophagus but cannot attach itself to cancer cells or those in the early stages of turning cancerous. This gives a clear signpost to where the disease is developing.
If caught at this stage, the cancer cells can be ‘zapped’ with an electric current which kills them without surgery.
The treatment offers hope to more than 8,000 Britons a year who are diagnosed with oesophageal cancer.
One of the patients in the study had their entire oesophagus removed because a small pre-cancerous area had been identified – which using the dye was found to have been very small and could have been treated without surgery.
Deadly: Oesophageal cancer is one of the most fatal because it is often missed or wrongly diagnosed until it is too late.
Two patients whose cancer had not shown up using the current imaging methods – which usually only detect when a tumour has formed
– were found to have clear areas which needed treatment.
Lead researcher Dr Rebecca Fitzgerald, of the Medical Research Council’s Cancer Cell Unit in Cambridge said: ‘Current methods to screen for oesophageal cancer are controversial – they are costly, uncomfortable for the patient and are not completely accurate.
‘Our technique highlights the exact position of a developing oesophageal cancer, and how advanced it is, giving a more accurate picture.
‘This could spare patients radical surgery to remove the oesophagus that can result in having to eat much smaller more regular meals and worse acid-reflux.’
Cases of the disease have doubled over the past 25 years particularly in men, thought to be linked to alcohol and smoking. Only 1 in 12 people survive for five years after diagnosis.
The researchers, funded by Cancer Research UK, tested the treatment on 80 biopsies from people with Barrett’s oesophagus, a condition which increases the risk of oesophageal cancer, as well as four patients with cancer.
They say the dye is ‘relatively cheap’ and unlikely to cause side effects as it uses a type of wheat germ protein found in our normal diet.
This binds to glycans, sugar molecules on the surface of cells inside the oesophagus and they added a flourescent tag to make it glow green under light of a specific wavelength.
It can then be seen using an endoscope – an optical tube passed down the oesophagus.
When diseased, the glycans’ structure changes – and current imaging methods cannot pick up these tiny changes.
The test needs to be trialled on newly diagnosed patients but the researchers, whose study is published today (Mon) in the journal Nature Medicine, believe it could be used routinely on patients within five years.
A UK trial is already being planned.
Dr Julie Sharp, senior science information manager at Cancer Research UK, said: ‘Oesophageal cancer is one of the most difficult cancers to detect and treat.
‘We urgently need new ways to detect the cancer earlier, and this dye offers a great opportunity to treat the cancer more promptly and more successfully, potentially saving many lives a year.’