Scans involving magnets can now monitor breast cancer tumours in real time and reveal which parts of them are growing fastest.
The imaging technique, which has been used in humans for the first time, involves making one of the body’s own chemicals magnetic and scanning it with an MRI machine.
The magnetic field comes from a chemical which tumour cells naturally use up, so the rate at which it disappears shows how active a cancer is.
This can help doctors to work out the type of cancer someone has and how it’s acting at a certain point in time.
Cancer Research UK’s Cambridge Institute led the research and tested the method on seven patients at Addenbrooke’s Hospital in the city.
Breast cancer is the most common form of the disease and is diagnosed more than 55,000 times every year, causing more than 11,000 deaths.
Some people’s cancers are more aggressive and grow or spread faster than others.
Using the magnetic scan, scientists will be able to tell how fast someone’s tumour is growing and therefore work out how urgently it needs to be treated.
It works by making a naturally-occurring chemical, called pyruvate, magnetic and then injecting it into the patient’s body.
Cancers naturally burn up pyruvate to create energy and make building blocks for new cells – potentially cancer cells – to be created.
By placing the patient into an MRI scanner, experts can watch in real-time how fast the tumour is using up the magnetic pyruvate and therefore how fast it is growing.
Understanding the internal workings of a tumour could help doctors get treatments extra precise and avoid patients being under- or over-treated.
‘This is one of the most detailed pictures of the metabolism of a patient’s breast cancer that we’ve ever been able to achieve,’ said Professor Kevin Brindle, the lead researcher.
‘It’s like we can see the tumour breathing.
‘Combining this with advances in genetic testing, this scan could in the future allow doctors to better tailor treatments to each individual, and detect whether patients are responding to treatments, like chemotherapy, earlier than is currently possible.’
In their hospital tests, the CRUK scientists were able to use the scans to identify the type of cancer someone had, how big the tumour was and how aggressive it was.
They could also produce a map of a single tumour, showing which parts of one growth were most active or developing fastest.
For the imaging process the chemical – named hyperpolarised carbon-13 pyruvate – had to be frozen and exposed to extremely strong magnets to make it magnetic itself.
This made the signal it emitted when scanned in an MRI machine 10,000 stronger than usual and therefore easy to see.
‘The simple, non-invasive scan could be repeated periodically during treatment, providing an indication of whether the treatment is working,’ said Professor Charles Swanton, Cancer Research UK’s chief clinician.
‘Ultimately, the hope is that scans like this could help doctors decide to switch to a more intensive treatment if needed, or even reduce the treatment dose, sparing people unnecessary side effects.’
The findings of the tests were published in the journal Proceedings of the National Academy of Sciences (PNAS).