They hope the inexpensive and simple test will spot the disease long before a woman develops a lump – and say it could be used in a national screening programme.
Picking up the cancer at the earliest stages when it is easiest to treat could save thousands of lives, as well as spare patients and their loves ones the pain and distress of prolonged illness.
Researcher Fiona Larner said: ‘Prevention is better than cure.
‘There is a survival rate of about 80 per cent for breast cancer but the earlier you can detect it, the more chance you have of treating it.
‘There are drugs out there that can cure breast cancer or give patients a better timeline.
‘If you can detect it earlier, you can give more women a better chance of survival.’
The hope centres around the metal zinc and ‘heavy’ and ‘light’ forms of it which exist in the body.
Breast tissue is known to take up zinc and release it back into the bloodstream.
Dr Larner has shown that cancerous cells absorb more zinc. They also hold onto more of the ‘light’ form of the metal.
If breast tumours have more of the ‘light’ version in their tissue, this means they unwanted ‘heavy’ version should be floating around in their blood.
In other words, woman who has higher than average levels of the ‘heavy’ form of zinc in her blood may have breast cancer.
Dr Larner is developing such a blood test and hopes it will be available in as little as five years.
Women who have inherited genes that put them at high risk of breast cancer are likely to be first to benefit.