The end of invasive biopsies? Scientists create wearable device that captures live cancer cells in the blood and works three times as well as a syringe
- University of Michigan researchers have developed an electric screening device
- It collects cancer cells over a period of hours instead of from a single sample
- The scientists say it can collect more than three times as many as a blood test
Cancer cells could be collected by a small wearable device plugged into a vein instead of a blood test or a biopsy, according to scientists.
Researchers have invented a small blood screening machine which they say can harvest more than three times as many cancer cells than a blood test.
The watch-sized device works by hooking up to a vein and capturing cancer cells as they pass through it, instead of drawing a pool of blood and hoping to find some.
Tested on dogs, the gadget could be, in medical terms, the difference between CCTV which takes regular photos and that which records a video.
The wearable machine (pictured) plugs into a patient’s vein to collect cancer cells continuously over a long period of time instead of relying on a single sample from a blood test
Scientists at the University of Michigan have created a prototype of the device, which they hope will make cancer diagnoses more accurate and less invasive.
It’s important to measure cancer cells in the blood, the team said, because those roving cells are the most dangerous and most likely to spark new tumours.
So people with high numbers of circulating tumour cells may be more likely to have dangerous cancer which spreads – the metastatic kind.
And because many cancer cells can’t survive in the bloodstream, it can be difficult to find them.
Sometimes traditional blood tests, which may only be of only a tablespoon or so of blood, can miss them completely, the researchers said.
Lead developer Dr Sunitha Nagrath said: ‘[This is] the difference between having a security camera that takes a snapshot of a door every five minutes or takes a video.
‘If an intruder enters between the snapshots, you wouldn’t know about it.’
Aside from drawing blood from a patient’s vein, another common method of getting living cancer cells is to take a biopsy.
This involves cutting out a sample of a tumour, usually under local or general anaesthetic, and sending it for lab tests – it is an invasive surgical procedure.
The team tested their device on dogs injected with human cancer cells, which are destroyed by the canines’ immune systems within hours.
For the first two hours after the injections the dogs had blood screened by the continuous machine and in blood samples taken every 20 minutes, then screened by a similar machine.
The continuous testing gadget found 3.5 times as many cancer cells per millilitre as the more traditional method.
And it is small enough to be worn on the wrist of a hospital patient, who could be hooked up to it for a couple of hours to provide a sample.
Dr Tae Hyun Kim said: ‘The most challenging parts were integrating all of the components into a single device and then ensuring that the blood would not clot, that the cells would not clog up the chip, and that the entire device is completely sterile.’
To overcome this, the researchers mixed blood with anti-clotting medication heparin inside the machine.
Dr Daniel Hayes, who was the senior author of the paper presenting the findings, hopes human trials can begin within the next three to five years.
He said: ‘Nobody wants to have a biopsy.
‘If we could get enough cancer cells from the blood, we could use them to learn about the tumor biology and direct care for the patients.
‘That’s the excitement of why we’re doing this.’
The research was published in the journal Nature Communications.